The world has moved on in the sense that "good enough" and cloud eats into their balance sheets I'm sure, but there's loads and loads of banks and legacy enterprises that maintain their ivory tower data centers and there's nothing to replace these with AFAIK. Google has Maglev, AWS perhaps something similar, MS no idea, everyone else just buys F5 or doesn't need it.
My org moved off nginx for haproxy after we learned that (at the time, maybe it changed) reloading an nginx config, even if done gracefully through kernel signals, would drop existing connections, where haproxy could handle it gracefully. That was a fun week of diving in to some C code looking for why it was behaving that way.
we went in the opposite direction, not because haproxy was bad, just because nginx had a simpler config, and i think we were paying for haproxy but don't pay for nginx.
all that said, neither drops existing connections on reload
