I backed up all the old files minutes before the update went through. Pretty sure it can be played on LAN wit some tinkering, so also online with hamachi/gameranger/zero tier/radmin VPN.
But yea, the old matchmaking is gone now. It does make some sense to scrap it, so the player base doesn't get split, but an option to play 'legacy csgo' would be nice.
You can probably even rollout your own matchmaking for csgo. People did it for dota 2. There are older modified dots 2 versions out there where people have setup custom matchmaking servers (iirc)
But yea, the old matchmaking is gone now. It does make some sense to scrap it, so the player base doesn't get split, but an option to play 'legacy csgo' would be nice.