How effective are flashlights compared to tools and medkits?

Just to start off, I'm fairly convinced that flashlights are a relatively weak item. Yes, they have the potential to get a save, but generally speaking killers are normally able to avoid being blinded by flashlights by positioning themselves properly and being generally aware of when survivors may be attempting a save. And a survivor who is following a killer around hoping for a save isn't spending any time on gens or healing anybody directly, so effectively the killer is keeping two people from progressing the game for the survivors with just one chase. Also note that, even if you happen to think flashlight saves are consistent and effective enough, the game now also has flash grenades and such which can do the same function but just in a slightly different way.

As a side note, flashlights do have some other minor effects

• They can blind at pallets. This isn't normally actually that useful though, because in the time you took blinding the killer at the pallet you could have gained quite a bit of distance from them. So it's not really giving you very much typically for the effort other than a decent bloodpoint scoring event. (Which, admittedly, it's not a bad amount of bloodpoints for that event if you care about that sort of thing.) That being said, the new survivor perk on the PTB which hides all your scratches, blood and sounds if the killer gets stunned means you could hypothetically stun them, blind them, and run for the hills with them having zero idea where you went. So with that perk it could be a reasonable combo.
• Flashlights impact certain specific killer powers. They can erase Hag traps, destroy Artist Crows, stun Wraith out of phase, stun Nurse out of a blink (although that one is probably very difficult!), stun Nemesis zombie, and destroy Spirit's husk (which isn't hugely important probably but it's a thing.) Certainly if you happen to face a Hag, for instance, a flashlight is useful. However, how often does that happen? Unless I overlooked something I think there's only four or maybe five killers if I'm generous where this is a non-negligable factor, against the other 21 or 22 killers there's no killer specific weakness to them. Is it worth bringing a flashlight on the 20% chance you might run into a Hag, Wraith, Nemesis or Artist? And even if you do, if it's not Hag to get rid of her traps, is it better than the tools or medkit you could have brought instead? I'm pretty skeptical.

So I'm not saying flashlights are "bad" necessarily, but I definitely think they're relatively weak items when compared to tools and medkits. They're probably better than keys, at least in consistency, although hypothetically when a key works it's a free 5000 point escape so those are the definition of high risk, high reward items. Maps might be the only item as relatively weak as flashlights, and even then you could argue that depending on the build maps could be useful for sniffing out the totems for example, maybe.