Hi Hayato,
You caught me on vacation and I'm only recently returned now to a massive pile of work. This might take a little while to put together, especially given the size of this feature (I'm four links deep now and I still can't answer the first question I had).
I do want to make it clear that there is a distinction between what we think of the current shape of the proposal (our response in [2]) and whether we agree with you that shipping this feature is a good idea. This is a massive chunk of work that - despite you working in public on it for some years now - is still essentially proprietary. Shipping something in that state is something we might object to, even if we end up liking the specification[*].
Cheers,
Martin
[*] Note that I think that us liking the specification in its current form is unlikely. I found an issue with the CSP section just skimming through the explainer.