> For example, you can still play games like Master of Orion 2 or Total Annihilation in multiplayer, because they rely on players hosting servers, and some people still host servers 25+ years after release (and people have even written fan patches to make that possible today, if necessary).

You make it sound like a good thing. And it indeed is for gamers. But it's the worse nightmare for established dev/pub that people play the old games, on their own servers, instead of your latest title.

It actually happened quite a lot. Starcraft I was (is?) more popular than Starcraft II in Korea, where the biggest Starcraft E-sport scenes are. I recently learned that Red Alert II is still fairly popular today in China, and Red Alert III players don't exist.

"How to out compete our previous title" is a real problem that established studios face. The lack of durability is a "solution".