I think it's a nice idea, but it just won't happen.

The game companies won't offer managed game servers, because it's a totally new, small-market line of business outside their core competency. They won't open-source the server and let users run it themselves, because myriad licensing/IP/legalese reasons. Even if they did open source it, the stack likely isn't designed to scale down to a few bucks a month on the public cloud -- most users interested in running their own server wouldn't be happy with the actual cost of doing so. The handful of folks willing to pay for it won't move the needle.

Nobody's asking for "managed servers" they're asking for server binaries, which can be easily released without source code and was common practice for decades before games turned into live services.

You make it sound like this is a hard problem that studios don't know how to solve, but it's been solved for decades. There's still a bunch of third-party Quake III Arena servers you can play on, for example.

Selling managed software is definitely a hard problem that game studios don’t have expertise in. It’s cool that the community reverse engineered Quake’s server, but that doesn’t mean it’s trivial for all studios to offer server software for their titles.

Implementation aside, I think it’s primarily a money thing—the studios don’t care about this because the numbers say they shouldn’t.

There are third party Quake 3 servers because it _was_ trivial for the studio to offer server software for their title.

The community didn't reverse engineer the server. id Software released it.

That’s cool, I’ve never played it. It’s one game from 20 years ago.

It's far from the only game that works like that, and the fact that publishers have been able to do this for 20 years was my point.

Even peer-to-peer multiplayer was very common. That is sufficient server software was included in the game itself. No need to download or run it on a server.

Online-matchmaking becoming more and more centralized really made this starting to go away... It has both good and bad sides. One is much larger player pool and automated matchmaking. Other side is losing communities and more custom servers with custom maps...

Minecraft, Terraria, Rust, ARK, Arma, Chivalry, Valheim, Factorio, most Valve games.

Almost all multiplayer games were like that, it only changed with the coming of MMOs.

as drew says - i am asking for binaries that i can run on a VM, just like minecraft or csgo

i dont need a source code, i need a binary and a config file, some decent error logging and some basic documentation with how to get it running/common issues/requirements

that's it

The problem with this is, dependency updates, security fixes. Software needs to be maintained. Releasing source code or a good protocol documentation ensures this happens.