You specifically said “online servers for authentication”. That’s what I understood as just that - a server required to be able to play the game, not a server required to use an actual online feature of a game. Don’t get me wrong, I very much prefer when games allow multiplayer games without requiring a server run by the publisher. All that is very different from what the posts title is about, though.

By the way, there are still games on GOG that let you run local servers for multi player gaming.