What I don't understand is why search is so broken.

If I do a search of my inbox with a lot of results, it gets lazy-loaded. Fair enough. But why, when I scroll to the bottom and it loads the new batch of email, does the view need to jump back to the top of the list?

Why has Gmail been able to recognize and properly group/deduplicate prior conversations in top-posted email threads for 20 years, but Outlook can't bother? That also breaks search, since every email with the result somewhere in its body (even prior emails) will appear.