I kinda get your friend. I accidentally skipped S3 part 1 because I couldn't remember anything from S2. The anime is really tiresome in the beginning and it only really picks up in S3.

That being said, after "The Basement", I almost dropped the whole thing because I thought the swerve was super dumb.

Fortunately, I decided to read the manga (something I haven't done in decades) and after reading through what I skipped and refreshing my memory on what I had forgotten, I finally got it. All the foreshadowing and hints were there but I didn't pay attention. What I thought was just a dumb shonen anime turned out to be something pretty cooler.

This anime has the same "problem" as Westworld, in my opinion: people skip forward through a lot of things, they lose track of the story, they stop understanding what's going on, and they complain the show is complicated. To those that watch closely and pay attention, the show is very rewarding (and fun).