It's awesome it exists, but useless if nobody uses it. I think the Google homepage is the only Google product I'm aware of that loads fast, minimal CSS and still loads without JS. Even on a modern computer, some websites have become completely unacceptable to run in the background (i.e. Facebook).

Installing NoScript and blocking external CSS was the best decision I ever made. Now use <25% of the RAM and <10% of the CPU I used to for the same number of tabs (in Firefox) - with a better experience because the browser isn't constantly trying to die.

The UK Government site team is my go to for a good web design philosophy: https://www.gov.uk/guidance/government-design-principles (Hell, if they could run the actual Government like this we would be in a lot better shape!)