Wow, this is probably the greatest article in 2020 so far.
Well written. As i'm reading my own workflow transition..
Blocks are the future, wether you like it or not. I didn't like it at the start, now i see the enormous power and possibilities.

A few things to say about javascript: that knowledge is not needed for the majority of 'webdesigners'. HTML, CSS and PHP is enough. I can't write javascript, but i can build almost everything. Thanks to PHP, snippets AND the live-saver-tool called ACF.

About full-site editing: i don't believe in this feature (yet). Mostly because of the header. For basic sites with basic navigation that would be OK. But out of the box, WordPress never ever will come close to the options that WPAstra of Kadence Theme have. So, i don't see the point to invest so much time in here.
The Block Editor is a content editor, leave it like that for the moment. WordPress must focus on that, cause there are a lot of shortcomings of options for a 'content editor': padding, margins, differences in responsiveness...

Why i'm suggesting that focus? History is repeating itself. Elementor got the become kings cause WordPress lacked the content editing aspect. Now, a few others are in the block-design-race to become the next 'Elementor' for blocks. It will be just a new 'ecosytem'. And any ecosystem has one big minor thing: locked-in issues. And i always believed Gutenberg gonna solve that locked-in effect, as a few times stated on State of the Words. But at the moment with these number of 'design' options in core, (the desktop-focus only): it's just shifting the locked-in to other plugins like Ultimate Gutenberg Add or Kadence Blocks. So, i really hope that i can rely more on core blocks in the future for designing websites (without adding classes which client's don't get)