[The Alpha Bat]

I feel like this is homogenization and that's something I'd rather avoid to be perfectly honest. Some races and abilities will always synergize more with some classes and so on and so forth, I don't actually think that's a problem.

Almost full disagree.

This wouldn't be a case of homogenization. There's a difference between everyone playing everything exactly the same and everyone being able to actually (successfully) play what they want. If anything, it's the opposite. Non-Theno Corrupted races would be able to keep up competitively while playing Dark Bard. That's more variety, not less. Unless your issue is with dark bard being really popular right now because that's a different issue entirely.

As for synergy, I think it very much is a problem, albeit a minor one. In this case, however, it's a larger issue because it's not about synergy. It's about anti-synergy. This isn't the same as bird races enjoying their free Gain Air with classes that like to be airborne, this is a race's and a class' core mechanics being at odds with each other. It's not a lack of bonus, it's exclusion. Being able to combine races and classes in whatever way you want and still find relative success has always been one of the game's draws and we're sort of losing that here.

Just build SAN on your corrupted. Start playing a race because you like their lore.

I've yet to see a compelling lore reason why corrupted races are worse at hurting things with sound magic than others. You can play whatever race you want for RP but that shouldn't mean you have to suffer mechanically for it.