I also switch back and forth between two large projects written in different decades and it definitely gives an interesting perspective on this. Basically every time I'm in php I go "oh yeah I see why we do react now" and every time I'm in react I go "oh right I see why php still exists."
I switch between a fair variety frontend, backend myself and have never had that reaction.
It's always, I could do exactly this in 2005 using jquery + JSP, it would not need any of these 1500 dependencies and the user would see absolutely no difference (except downloading 10 times more js today at 5G speeds)
The scalability issues non-facebook scale webapps are trying to solve for do not exist. These apps will be dead before they reach a 10% of that scale and yet the project folks just don't get it.
anecdotally, github project bookmarks I have 3-4 years ago won't even compile today. a large chunk of projects from 2010 still work. Including mine I wrote a decade ago as a newbie js junkie.
