SSR with CSR is a worst-of-both-worlds approach. It leads to brittle ”isomorphic” behaviors when the same code needs to handle both SSR and CSR, inevitable client-side ”hydration” mismatches and various other issues. The same code needs to fetch eagerly but minimally, but also use and update the server-provided data on the client-side.
Ultimately that so-called ”isomorphism” causes more numerous and difficult problems than it solves.
Especially cuz the vast majority of sites can either just be client rendered SPA's or server rendered multipage apps. There is no need for the complexity for most sites and yet this is the default for pretty much all js frameworks...
Sounds a little like hooks.
A purist approach with short term thinking got everyone deep in a rabbit hole with too many pitfalls.