I personally have no obsession with including everything but the kitchen sink, but if you spend any time with real SPA codebases out in production at real companies you will find that is the case.
This absolutely is an opinionated post because I'm extremely tired of slow to load, slow to execute, and often buggy software! Apollo 11 made it to the moon with 1MHz and 4KB of RAM. There is absolutely no fucking excuse for typing plain text in an input to lag on my computer with each character.
If you're not scared of complexity the fantasy will end soon enough.
The main point is, there's a lot that is not either right or wrong in Information Technology. You can be considerate of users and also have a great experience - the two things just aren't mutually exclusive. You seem to be assuming a lot about what goes on in any team that is working on a frontend product.
I'm currently working on a project that matured from recognizing the limits of server-side applications for example. My users are tired of having to refresh to fetch data, tired of not knowing what is really going on or just end up waiting without a reason, and most definitely want drag&drop, instant previews, offline capabilities and WYSIWYG. I can't walk up to them and say "well guys, nope, we're moving to something that is even less reactive than Wordpress" and not get immediately thrown rocks at.
Whatever rows your boat, I'm happy for you. I guess you live in a place where you can do whatever you want without any repercussion. I live in a place where I most definitely can't deliver a 2006 experience just because I feel entitled to burn my company time and money on my ideological wars about what they need or not need and call them lazy.
Perhaps we have different visions: you want me out of business, I'll read what you do and take note to improve my design. You're so sure the web is not for apps, I love that the web is the great equalizer where no one can tell you what you can or can't run. I'm not afraid of complexity, I'm afraid of what happens when people decide their own bias about tools are more important than a job well done. I shouldn't even call that complexity honestly, because there's no black magic behind React or anything. And if you find my 200 kilobytes to be too much, please, just download the fuckin' app and bye bye.
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