Thank you Auryn Macmillan for the responses! Really appreciate it. So I think Bryant Eisenbach sort of gave a great summary of what I was trying to propose here: https://twitter.com/fubuloubu/status/1106273734141317120

To quote him(!) All of this is “part of a non-binding framework where this is used as a signaling mechanism” i.e. it’s opt-in. That I hope at least answer 4 and the reasons why it’s separated out from Ethereum itself.