GOG Galaxy is a frontend for a whole bunch of game stores, including Steam and Epic. Even does things like messaging and activity reporting cross platform. On the Linux side I know Lutris does some Steam management.
You can use the command line version of Steam to do some stuff, but because that’s the only real API, all alternative frontends involve installing some version of Steam.
GOG Galaxy is a frontend for a whole bunch of game stores, including Steam and Epic. Even does things like messaging and activity reporting cross platform. On the Linux side I know Lutris does some Steam management.
You can use the command line version of Steam to do some stuff, but because that’s the only real API, all alternative frontends involve installing some version of Steam.
Playnite would be in the same category, I suppose.