Artist results differ depending on how you get there

Your first screenshot is the Composer screen.

The third one with more results is the Artist page.

The Composer pages probably make more sense in the classical world, but I find them less helpful than the Artist page with contemporary artists.

There’s also this known bug to complicate things further, where if you don’t have an Artist in your library already, you can only get to the Composer page and the option to switch to Artist isn’t available.