I think gaming is particularly interesting in how different genres originated from technical limitations as much as anything, and so have maintained designs that simulate situations we now have the technology to just depict in order to preserve the genre - you were kind of right in that metroidvanias are designed to create that perception of a big, open, connected world, and we now have the technology to make open world games, but metroidvanias are actually designed as very tightly developer controlled experiences that steer you through a maze along an ultimately linear path between upgrades and/or bosses. The connection between exploring the maze and unlocking more ways to explore it are really the core gameplay loop, so dropping either part changes the most important parts of the game.

I think open world games can pull some ideas from metroidvanias, but I can't see a way to square the circle of making a maze without the maze.