Everyone just loves untested forced updates. /s
I don’t have anything mixed up and you’re not right. The mod was only pre-Valve when it was still in beta. They hired Minh right around Beta 5. When Valve made CS 1.0 (way before CS 1.6) part of the official Valve catalog, they set up official servers but you could still set up community servers. When Steam came out, they required that it be run through Steam which forced everyone onto the same version of both the client and the server. You could still spin up your own server using an older version but you the game wouldn’t be listed in the game’s browser. You had to use Gamespy or HLServerWatch.
Steam forced everyone to update. It’s not 100% analogous to this situation but going from mod to standalone fractured the playerbase and codebase. This was clearly a move to prevent that from happening again. I’m indifferent to it but obviously everyone isn’t.