It can be convenient. You’re going to launch the games somehow, whether that’s clicking files in a folder or running a command. If you have a bunch of games it’s nice to see them neatly organized in one place with nice visual representation. Non-launcher options tend to either get unwieldy or require more customization work.

The Steam launcher does a whole bunch of other useful things, like managing saves, setting up Proton, tracking play time and achievements, connecting to friends, integrating the store. It’s not hard to see why people like the convenience.

It is annoying when it goes too far… like individual games that insist on having their own launcher.

Heroic is a nice middle ground. GoG gives you simple downloads, that you can then choose to access through Heroic.