I also find it annoying that it seems people have transitioned from progressive enhancement meaning 'detect if we can use JS' to 'detect which features of JS to use' to 'detect how much processing power we can abuse without the user noticing'.

As someone who really enjoys his <0.3s page loads (that is fully fetched & rendered, less when from cache) even on mobile it feels annoying to not have a 'middleground'.

For example my current project, which is basically a small website where people can upload artwork, does not need to be a SPA. However, I'd like to integrate some interactivity to make browsing easier. Like a 'browser' view when you click a picture, or in place reloads (so the CSS doesn't need to be reloaded, nor perhaps the JS. However there doesn't seem to be a library for that to my knowledge. All I know are either on the jQuery level where you have small seperated pieces, or the React/Ember/Angular level where you have to write all or nothing in that language.

I wonder if it is even possible to have an 'augmenter' library that just makes existing HTML better (Perhaps with some hints in the 'data-' attributes), or maybe my google-fu is just bad.