>However , In a business setting with lots of developers this usually becomes an abhorrently performing website despite the SSR with the same templating language.
I'm not sure this follows. It's harder to do client side rendering because your data is across a slow HTTP barrier. And the client is maintaining state which is harder than stateless.
The problem with SSR is that it's usually tied with single applications which are usually monoliths. But neither of these are requirements for SSR. If you break up your monolith into modules and/or SOA you get the best of both worlds.
But for reasons I don't understand nobody does it this way. It's either monolith + SSR or microservices + client rendering
