Not fixed.
I created a new world using the snapshot with view distance set to 5, difficulty hard. I had 2 players log in and run around, generating chunks, while I built a mob farm in creative. After the mob farm was finished, those players logged out at least 10 chunks away from the mob farm and I parked myself at the proper AFK spot in survival mode. The mob farm produced 2 rotten flesh, a bow, and 3 bones after running for an hour.
I don't think this will be fixed until there are fundamental changes to the hostile mob spawn/despawn code which adjust the 128 block mob spawning radius based on view distance on the server, rather than being a hardcoded limit.
[23:16:14] [Server thread/INFO]: Starting minecraft server version 19w14b
I'm using a FreeBSD jail on FreeNAS 11.2, if it makes a difference. I already have a 1.13.2 release instance running publicly, and have been running a server in some form or other since 1.8 dropped.