I've still not played Catan, but I've converted a few friends with Cascadia. Catan is the most controversial game I've come across, plenty of lovers and haters in equal measure
Catan is the Monopoly of adult board games. The first half is fun, then you figure out who's going to win, and the second half is just going through motions with no fun.
I honestly haven't run into that much with the group I play Catan with. Our games are almost always neck and neck, usually with someone stealing the win right out from another person that seemed to be the closest.
Although we have always played with the "house rule" that you can't play either of your starting settlements on a coast/dock, so maybe that helps with balancing. 🤷🏼♂️