Why are people trying to argue that Sion is a good Support now?

Braum is still a common ban in game modes that support that. I could see Sion being a situational support against a comp that couldn't interrupt his Q. But I think overall there are much better suppots than Sion. I think Sion scales best in the jungle.

That's generally not how the meta is formed, is it? The reality is that we have some weaker and some stronger champions, each with varying levels of power throughout the game. New Sion is a pretty weak laner with a moderately epic posthumous ult. If he goes bot, he can tag-team with the baby ADC to try not to die as quickly, and, especially in bot lane, if he gets killed he can pretty much guarantee they get something out of it.