Guess what? During the last few years, more and more parts of Steam's UI got rewritten to work in a very similar way to how Electron does (using CEF). Back when these views were still in the minority it was easy to identify them by how sluggish they felt compared to the rest :)
Not OP but on Mac at least I find it wayyy faster to browse the steam marketplace and community sites in Safari or Chrome than in-app. Everything about it is slow from loading pages to scrolling to clicking buttons.
Not OP, personally the Steam UI seems to freeze in the following cases for me:
- when opening or scrolling my library, as the icons load in (~400 games)
- when trying to install a game (delay until the install dialog pops up)
The other slowness feels inconsequential, like when opening a store page or launching a game - on par with what you'd get when an average web app is loading or an Electron app is being launched.
Pretty much every other store out there has been worse in comparison, GOG Galaxy seems to be reasonably close to me though, Origin and Epic are both slower in my experience.
OS? I don't have freezes, with more games (though most are in closed categories). Galaxy is second best for me as well, but it's also the only other app trying.
I don't remember any install freezes, but I wouldn't bet on that one.