My head hurts just thinking about react.
But that is just the beginning of the process, the job is barely half done.
The devs must then focus on exactly what is needed in the code to refactor and strip out every unnecessary instruction and byte of download.
Page load times and refresh times that are more than 3-digit milliseconds rapidly become unusable. When it is 5-dicit milliseconds, on a modest machine, you are shipping junk, and should not consider yourself a developer. Amateurs can do better.
Wow, do I miss the days of the 5KB web page competitions...
The idea is that these libs and framework make an honest attempt at making web apps. Also well intentioned but wide off the mark. Most people access the internet through mobile phones[1] with dodgy broadband connectivity, hence don't need an app running inside another app - do you understand the redundancy and the pitfalls of janky, horrible UIs for the marginal performance improvement? Or the famous It doesn't reload the whole page...very few people actually care about.
If you are building the next instagram, go right ahead and use bleeding edge js frameworks, but not every site/blog needs to be an app.
[1] https://gs.statcounter.com/platform-market-share/desktop-mob...
Except that I'm not even sure that the next Instagram or whatever should be a web app - it should be a native app.
I saw the beginning of the "write once - run anywhere" concept decades ago. Sounded fantastic. Yet here we are and it is more like "write once - stumble and crawl someplace".
It is most discouraging that many major houses do it so badly, and even their native apps are similar bloatware...
And yes, that makes a difference, you can deliver more features, faster, more reliably.
But, if those sites just bog down and take double-digit seconds to load, even when properly deployed on scaleable delivery architectures, with fiber-optic speeds, and CAD/gamer-level power machines, they are junk.
And I increasingly see exactly this junk been over the last few years. Even (and often especially) the major sites are worse than ever. For example, on the above setup, I've reverted Gmail to the HTML-only version to get some semblance of performance.
Sure, some of this could be related to Firefox' developments to isolate tabs and not reuse code across local containers and sessions, but expecting to get away with shipping steaming piles of cruft because you expect most of it will be pre-cached is no excuse.
Your site might have the look and features of a Ferrari, but if it has the weight of a loaded dump truck, it will still suck. If you are not testing and requiring good performance on a rural DSL line and mid-level laptop (or similar example of constrained performance), you are doing it wrong.