None of this changes simply by moving rendering to the client, and none of these changes would require a client-rendered site.
In the context of the comment to which you're replying[0] I'm not sure how else to take your comment. OK, you don't like HN's UX, that's either a comment on SSR and on topic for the thread, or completely unrelated.
> HN as a site is a perfect example of how bad a SSR experience can be.
This is a great ending line if the things you list before it would automatically be better under CSR, or are only capable of being fixed by moving HN to CSR. So, it seems pretty natural to me to assume that you're saying those things (reply notifications, typography, losing position on a reply) would be better under CSR, which is not necessarily the case.