For me it’s first person puzzle games. I can think of maybe a dozen off the top of my head that came out in the last decade. I especially enjoy when they’re open world. The ability to just quit a puzzle that’s stumped you and go try something else for a little bit is incredibly refreshing.
If you like puzzle games have you played the entropy center? Its better than portal IMO
I don’t know what kind of game entropy center is, but puzzle is IMO not a wholly useful term, since there are different kinds of puzzles and portal falls into the physics puzzle subgenre. There probably are other fpp that aren’t based around physics, but I can’t think of any right now.