I’m sure you could make something work better as a SPA, but nobody does.
Github's code view page has been unreasonably slow for the last several years ever since they migrated away from Rails for no apparent reason.
Available data confirms that SPA tends to perform worse than classic SSR.
I’m not a frontend dev, and have next to zero experience with anything beyond jQuery, but an analogy is shell. Bash (and zsh, though I find some of its syntactic sugar nicer, albeit still inscrutable) will happily let you do extremely stupid things, but it also lets you do extremely complicated things in a very concise manner. That doesn’t mean it’s inherently bad, it means you need to know what the hell you’re doing, and use linters, write tests, etc.