You can't see replies on Twitter links anymore, though that doesn't really matter in this particular case.
Of course, who knows what it'll be doing tomorrow. I'd definitely think it's probably time for HN to prefer Mastodon (or Threads, I suppose) links, where a post is available on multiple microblogging things; Twitter has had any one of about five behaviours for non-logged-in linked tweets (work properly, work but without replies, spin forever, redirect to login, generic error page) over the last week, depending on when you try.
