I play Pokemon casually, meaning I've finished every game but I don't get too deep into the complexity of stats for true competitive play.
I still think RBY is a great place to start, as long as you have tolerance for dated games. The GBA remakes are more ideal, but the original Pokemon games are just as fun, accessible, and charming as they ever were.
I don't know if that's true. I feel like you need to be in a certain frame of mind to enjoy them today if it's your first time playing them. The glitches that negatively affect gameplay that we never noticed as kids would be pretty obvious to an adult.