I mean it’s a single equation. I hope that wasn’t the make or break of it for you.
But two things
1) earthbound sucks. Like, it has some very cool ideas with the rolling hp, visual encounters and auto beating trivial encounters. But I recently gave it one more go and while it’s got charm for days I’m just not into it.
2) I would say in general a lot of games have a lot more complexity going on in them than people tend to see. But mostly it’s not pushed. Sailor moon has a lot of weirdness going on I had to understand because it was unclear but it does boil down to “use cluster formation and put your damage dealer in the middle.” So for all that complexity the actual play is extremely simple.
I think if you play one of these without the manual you are being set up for failure. That might be a fault of the game or not but I think the earthbound manual might help with some of those clarity issues.
But at its core earthbound is a simple dragon quest clone with a fun setting twist.