What happened to alternate shells? It's still possible to change the environment launch app in environmental variables, but I haven't seen a different start men

What happened to alternate shells? It's still possible to change the environment launch app in environmental variables, but I haven't seen a different start menu or shell since around Win7 days. If this was possible, along with an update system that doesn't bring down even the "server" version of the OS, it would be essentially production ready.