Why am I seeing so many people attempting to use Taliyah as support today?
Its just as bad as it was on release (better read: worst role).
Please stop. There's very few ways she can interact with bot lane outside of W without blowing her entire mana pool. Her follow-up as support is extremely poor if she manages to land W, and it will often be to your detriment, barring ganks.
and your damage will be pretty low because you're not stacking ap on minions either.
supports. is it better? obviously not. but has it's own strengths.
too many people say "you wont be doing damage because you are support", which is false. Yes you are dealing lower damage because of level disadvantage + less AP. But you are not competing against their midlaner, you are competing against their janna or something, and you are dealing for sure more damage than their Janna.
A lot of off-meta supports really could work well, but people don't give it a try