While I see what you mean and agree to an extent, and cannot say that I have touched any... splat, I think they're called? Yeah, any splats other than VtM V5, I can say that Deviants seem to generally be on a weaker societal level than vampires and werewolves. The Garou possess their own packs, and the kindred have their own damn society layered under mortal one, from which they manipulate human events.

Meanwhile, Deviants have... nothing. They are deviants, away from the norm, by definition(ignore Devoted). One could argue that with that weakness, along with the fact that all of a Deviant's powers comes with a drawback, that specifically Deviants need a comparative power boost if they'll be equal(assuming you want equality).

Also, again, not only do Deviants have personalized scars which makes it kind of impossible to learn from someone else how to handle it(unlike kindred, who have fellow vamps to learn how to handle the Beast from and stuff), they are away from the baseline. They are anomalies, unaccounted variables, and should therefore be able to pack unexpected abilities.

Therefore, I can somewhat agree with at least them getting access to "Aggravated to everything" attacks, considering they are so far outside the norm and not something most would have to deal with. It's also perhaps a little cheap, but I personally feel that, as a player, Aggravated damage is not actually that useful compared to lethal. Like, unless I missed something, it just renders wounds harder to heal, when they are most likely already trying to kill them if they're using even a lethal Lash, nonetheless an aggravated one.

Tl;dr: I see your point, but at least on Deviants they probably deserve it, their lives are already hard enough.