>>41550016On lesser hardware, no less.
Anything is a straight line if you're doing it as direct as possible, the point is to have lots of shit to do to make you stray from that line.
The way Gen 1 and 2 were set up, the level design is closest to something more like DQXI or Xenoblade Chronicles 2. Their maps are still technically hallways if you don't care about extras but they're more appropriately sized for 3D modeled characters and there's a bunch of shit to do and find off the beaten path (a path which, again, is not a box three people wide at most in most cases) regularly.
Meanwhile Game Freak is doing Game Boy map level design - sometimes with rounded edges!