I have consoles and a powerful gaming PC. I use both regularly. For me they’re good for different things.
My Nintendo Switches get the most use.
Once you buy a prebuilt machine you're losing a good chunk of the savings that people talk about when buying a PC. You also don't just install steam, you have to install drivers, and maintain an OS (which doesn't have a controller friendly input method) so you need a keyboard and mouse around for windows update time or driver update time.
You mean you buy them from Steam, you launch a third-party launcher from Steam and launch your game through that launcher. I know that at least EA and Rockstar force you to use their launcher even if you buy on Steam and Microsoft also requires you to have Xbox stuff (at least for Forza Horizon).