Why almost everyone said blood moon event is survivor sided?

Just killers being killers that is all. The amount of BP you can get as killer compare to survivor is so crazy that means me being 80% survivor main will not be touching survivor and will easily get my p 80 Trevor to 100.

Survivors get bloodsense maps, but thats it

It sounds like your refering exclusively the soloq. In solo people don't usually gen rush, they actually avoid gens because it's boring. But SWF that play to win absolutely do gen rush, they also have no need for anti slug perks or info perks due to the fact they get these from coms.

The reason why the event is survivor sided is because swf in particular don't need gen rush builds as it's basekit with the speed of the new blood gens, they don't need info perks as they use coms so they are free to all use chase perks without compromising anything like info or gen speeds. Makes downing people very difficult. The ghoul is the main issue here, incredibly OP and new so survivors are dropping fast. But without ghoul I would say the event is very survivor sided. It just so happens many solo players don't touch gens which means killers are tearing people apart.

I'm gonna be respectful to both sides here, and I'm going to be direct, too. It's because of the Blood Gens and how they work. They give Survivors too much pressure against most Killers on the roster because of how they are. That's what makes this mode Survivor sided.

Both sides cannot use perks like Fire Up, Blast Mine, or Unforeseen - perks that proc on gens but don't involve progressing them. This limits the types of builds you can do. nfortunately, while Survivors have a lot of different perks that can create functional builds, it's pretty common that for most people playing Killer, you need at least one gen perk. Most people aren't gods at Killer and most people do not just always play the S and A tiers, everyone else genuinely needs a little help on gens from perks. Disallowing gen perks, while understandable for a test run, nerfs most Killer players QUITE hard. Meanwhile Survivors still can keep strong chase perks and info, which often is meta as well. So it boils down to Killers not having their meta or their helper perks, but Survivors getting to keep all theirs, which biases the mode towards Survivor side.

Nobody can use tools or perks to push or hinder gens right now, but that does not really make a difference when these generators can be done in 2.5 cans in under 30 seconds if Survivors coordinate. These gens are much faster than normal generators are, and that can feel really bad when you're Killer and just trying to focus on chase. Now, some Killers may just want to do chase and don't care about the kills, and that's fine. But that's not the majority of players, most players are playing to win or at least try to win a bit. It feels stressful as Killer to play against generators this fast without anything to help slow them down even a bit besides a 5% kick. It's also not very fair to Killers that genuinely do not have mobility or do need generator perks to pressure well, Killers like Trapper or Nemesis for example. They just… don't get to play normally because setup takes too long, and the gens are half gone before they can start even getting the ball rolling.

This limits viable Killers for the event to harvest BP. You need to have some combo of mobility or split-pressure basekit, no other Killers really work here. It feels quite bad to run around and try only to have a round end before you can begin, so a lot of the Killers people may otherwise play - weaker Killers that give Survs a breather - don't get played.

It also means Killers feel the only way they can pressure is to play in very unfun sweaty ways - by engaging in more tunnelling and slugging, or by playing very strong Killers that excel at those things, in this mode. I have seen only three kinds of Killers this event: Hardcore sweaters who go nuts with the strongest Killers from the word go, and Farmers who don't really try. Oh, and a lot of the Ghoul. All three of those are quite boring after a while of facing them, which negatively impacts my experience as a Survivor because now I feel I have to sweat in case I get another angry Blight, which means this poor Myers who just wanted to jumpscare and farm a bit has to deal with me sweating. It creates a vicious circle.

Blood Gens often spawn too close to Blood Pumps. Other times they spawn too FAR from them. This can change how well Survivors perform in a way that isn't really very fun for either side, but quite often they spawn too close and that tends to favor Survivors a bit more. I for instance keep spawning right near Blood Pumps and not too far from Blood Gens. That feels a little rough for some of the weaker Killers. There is not a compensation effect to make these gens slower or riskier, the loss of blood for running isn't enough of a downside and doesn't slow the generator fueling at all, and the effect can be negated entirely if you run Fixated and walk with one. This means there is no natural risk to doing these gens versus a normal one, so that means Killers feel even more pressured to waste time kicking gens. And as we know, wasting time as Killer isn't good.

Bloodshot Eyes don't seem to grant points properly, especially for Survivor side, so you have to be aggressive with the gens as Survivor. This means someone may snipe your jerrycan, snipe finishing your gen, etc. Only the finishing Survivor gets the points so you HAVE to be aggro if you want any points. This means everyone slams gens really hard for points, which means efficiency, which is an issue for some Killers - they don't all perform the same with no generator control against coordination like this. That creates more pressure and stress for most Killers, and encourages them to pressure with what they have left in their kit TO pressure: slugging, tunnelling and camping, which most players fall back on because most players are not gods at Killer. This leads to unfun matches for Survivor.

Some Killers whose powers work on or can affect generators lose those aspects of their power, because these gens don't count as generators. For example Pig's headtraps do not work when the Blood Gens are done, and Freddy can't teleport to them. They lose fundamental aspects of their kits. It appears Knight's guards cannot kick these gens, and Plague cannot puke on them. Some Killers have addons affected - Ghostface's Driver's License does nothing to these generators, meaning he can't run this addon as it is useless. Some Killers with item spawns, like Sadako and Xenomorph, get their items messed with by the blood gens and pumps even though they use hook and gen spawn logic - they end up with dead zones or with their stations too far away to affect the blood gens and properly patrol for pressure, which is an issue for them. If people use things like Cobblers or coins, it affects them even more. That means these Killers are disproportionately affected and playing as them feels worse, so nobody wants to seriously play them in this mode.

The compensatory bloodpoints are nice, and you do get a lot more as Killer. If you can make the round last long enough to capitalize on it. But otherwise, there's nothing new or special for Killers here, and a lot of drawbacks unless you play really strong Killers or quite sweaty. It feels very stressful, and that's not a good thing.