Steam is the worst application on macOS I use. It can't even scroll the game collection at 60fps and when I launch a game without Steam open I need wait 15 seconds to see the actual game's loading screen or 30+ if Steam decides to update. It's so slow that if you told me it's emulating an entire Windows environment, I would believe you.

It's just an application launcher, a glorified Start menu. I would never choose to use it, it's forced on me because of the Steam store.