I think people who long for the "original" EPCOT maybe don't remember it or never experienced it. It was certainly different; imagine no Test Track, Soarin', or Mission: Space. I absolutely loved World of Motion and Horizons but it wasn't enough. It's not that Disney wasn't trying, it's that the model didn't work. There were only so many large corporations and countries that wanted to sponsor the different attractions and they only had so much of a vested interest to continue funding the attractions as the years went on. The Disney way is synergy and always has been. You may not like the Frozen overlay, but that overlay sells the Frozen franchise, and draws in the kids that already love it. That has more value to Disney than keeping the ride based on Norway, and Norway isn't paying for the ride going forward - Disney is. No kid is walking into EPCOT thinking, "boy, I sure would like to know a lot more about Norwegian culture", and racing over to the Norway pavilion to get their fill. For Frozen though, the race was on at rope drop, as was the character meet-and-greet next door.
The other thing I think you are going to see dramatically reduced, if not eliminated is the extensive pre and post ride experiences. Sure, you could spend an hour waiting to ride Test Track, but you could spend another hour going through the exhibits after the ride. The only direct benefit Disney sees from that is the gift shop right before you leave the building. Test Track, Mission: Space and Spaceship Earth all have sponsors that pay for those spaces (or at least they did pre-COVID) but I think Disney would much rather you moved on to the gift shop and on to the next attraction. Could be when the sponsor contract is up, you'll see those spaces change too.