I love Rust, probably one of my favorite games ever. However, playing on a normal server is pretty much a full time job. It seems that people either move onto something else or become entirely consumed by the game. Any games that are like Rust but aren't like that?
Like a multiplayer survival/crafting game with base building? Conan Exiles and Ark are the two big ones apart from Rust, and while they can be the same way they don't have to be.
I guess Valheim also fits to a lesser extent.
Ark is absolutely life ruining if you play on official servers. NEVER do this. Play on chill "boosted" PvE servers with friends
It's pretty easy to host your own Conan Exiles server. And it's a much better game than Rust. CW for all RE Howard's bs, though. They toned it down much for the game but Howard was still racist trash. But the core gameplay is a lot of fun especially if you like building huge castles.
You can also try Pathea's games like My Time at Sandrock. I haven't played them but I really enjoyed their older, very weird game Planet Explorers. You could also try X4 if you want something a little different. It's an economy sim in space, but it has surviving and crafting - You build your own space stations and fleets of starship to exert commercial and/or military domination.