That's only true to an extent. There are plenty of good well balanced, impactful survivor perks (look at exhaustion perks for example), and as a survivor in the regular mode you can easily put together a build of 4 perks that are all either consistently impactful or if they're niche or have requirements, are so impactful that they are worth having despite their nicheness/requirements. However these limitations are too extreme for a lot of survivor perks they are placed on, like hardened, all of the invocation perks, all of the teamwork perks, etc. The problem isn't that there are no good survivor perks. It's the devs are too afraid to make good survivor perks that they play it extremely safe with them and as a result there are too many perks that are near worthless.

This isn't about the power level of well designed perks, this is about the ratio of bad perks to good perks, which skews much more towards bad for survivor than it does for killer and it's because the devs are too afraid to let survivor perks be good, even if they have to nerf them later, so they always aim low

Yes a lot of survivors perks are completely useless without any synergy, I think that's correct too, most perks should be able to stand on their own as worthwhile usable perks without needing synergy to be a decent pick, Synergy should enhance those perks and make them shine, but a random selection of 4 perks shouldn't so frequently create actually worthless perks. Anti synergy is one thing, not everything needs to work with everything else perfectly, but a total lack of synergy shouldn't consign a perk to worthlessness. Many of the best survivor perks are good on their own but synergy let's them reach another level.

I will note that all of what I'm saying applies to killer perks too, but I think the problem is a lot more rampant in survivor perks than in killer perks.

The occasional primarily synergy focused perk like vigil on survivor or undying on killer is fine, but when so many perks rely on synergy to be even remotely usable it significantly hampers creativity and buildcrafting in limiting the ways perks can be used together, since those synergies are the only ways to make the perks work.

But that's not entirely true though because even outside the chaos shuffle mode you do not see people using these perks. The devs aim so low with the perks because they're afraid of making them overpowered that they end up useless. All I'm saying is they should stop aiming so low when they are creating new perks. It's okay if an occasional perk is out of band/OP. They can always just nerf OP perks later, but once these perks are released useless they're often doomed to stay that way forever because there's far too many older perks that need attention so they don't want to dedicate resources to newer perks even if they need the attention just as much as older perks.. The best builds always consist of perks that are individually useful. Requiring synergy to make a perk useful is basically sending a perk to be executed before it even had a chance to be good. If your perk requires 2 perks to compete with a single perk, it's basically always better to just run 2 other perks that are useful individually. Exceptions to that are very rare (buckle up before it got nerfed for example)

And of course this happens with killer perks sometimes too, but I think it's much more common with survivor perks, and it's a product of their design process, which I think is where the flaw lies.