X posts have a permanent url.
[1]: something like a link specifying the contents of my feed at a specific date+time and scroll-position.
…whereas with old-school SSR paging it’s right there in the querystring paging params (page-size, page-index or item-offset, and an optional results anchor for stability).
I’ll concede that a well-designed infinite-scrolling (or “click to load more inline” button) feature could use history.pushState to dynamically update the browser’s address with new query params but I don’t think I’ve ever actually seen anyone do that - which is a shame.
The only stable way to share what you're seeing is with a screenshot.
It's addictive. There is no "one more page and I'm done" because the page never ends and you're never done. You get to the bottom, more content loads automatically and people say "this looks interesting, let me scroll some more". That's why it's doom scrolling because all you do is scroll, no need for any other input. The bait is always there right in front of you and I'll bet that the algorithm make sure the first couple of posts that load every time you get to the bottom are the "juiciest" ones to make sure you take that bait and keep scrolling.
Pagination hides the juicy bait. It's still there waiting for you but it's hidden until you ask for it. That's a big difference.
An algorithmically "curated" TL, yes that's harder
Google search or a traditional paginated forum doesn't provide that either. No guarantee that page 15 of thread X will contain the same posts as it does now when the moderators wake up and delete the flame war.