Then you're going to have to answer: why did we lose dedicated servers in fps and LAN in modern games like starcraft 2, and many others.
Things that used to come inside the game, Descent 1-3, Warcraft 1-3, Diablo 1-2, quake 1-3 Doom 1-3.
All those games had multiplayer built into their exe's. So you have a lot of explainig to do why multiplayer networking has been ripped out of games like
Transformers FoC (an unreal engine game)
And games like Ridge racer unbounded
https://steamcommunity.com/app/202310/discussions/0/61282346...
Games from pre-steam era, multiplayer still work because they were embedded inside the exe. So you have a lot of explaining to do claiming "your mmo's" are special and I'm wrong, the easiest explanation is mmo's are just stolen PC games and they've been ripping out networking code once they realized you were computer illiterate/irrational to an insane degree in 97 with the advent of ultima online, lineage, everquest, guild war 1, asherons call and wow.
FoC is an unreal engine game, so why would we need to sign in to a remote computer to play multiplayer, when unreal 1, UT2003, UT2004, didn't require that? Or could it be those were all honestly coded local applications before the mmo-backend apocalypse infected all of gaming.