I can't look at an app and tell you that it's written in framework A or B, but so many websites are becoming dogs these days, and not just because they have to run Javascript. I think the scripts actually spend a lot of time blocking on the I/O that would have originally been delivered with the initial page. Server side rendering may be a solution but it seems lots of sites have a rather modular approach to putting components on a page that then load lazily over ridiculous amounts of time.

As an example, the American Express account management website. Lots of banking websites are going this way, where it's taking long enough to finish a request that you worry the logout timer will fire before it's done. They have also lost niceties like the ability to take you back to the same page with the items in the same order, that I had on the Dollar Bank website circa 1998. (Seriously, that bank was ahead of the curve and the website was fast, on 33kbps dial-up and a Pentium MMX 200.)

Other websites are the same. Kaiser. State taxes. Delta airlines. Formerly fast things replaced by janky lazy loads that reflow the page and cause you to click the wrong thing. And so much telemetry! Can you actually process all that data? Because if it's working it must be screaming that people are constantly clicking the wrong thing.