>>39696385>Or how in Zelda the only real progression is the abilities you unlockBotW was open world, didn't do that in the slightest, and did fine. You could literally start the game and walk to the final boss, but most people would get stomped every time they tried because of the shear skill necessary and the difficulty involved.
With Pokemon: you have the gyms scale to the current level the trainer is at based on the Pokemon caught and the average level of those caught Pokemon. At the center of the region is the Pokemon league, which requires all 8 badges to enter. And the Pokemon in the world could appear at a level above what the player has up to a point, but not above by a large amount. You could also use at system to tier encounters in zones rather than just say "everything here is set in stone". I mean, if you really want your limits, you have Pokemon only use HMs when you have the badges for them, still, but that wouldn't really be necessary if you built the world well.
I could see a truly open world Pokemon game working, it's in how you do it.