Huh, it's certainly an interesting subversion of Metroid games. I can imagine the pitch meeting: "what if we made a Metroid game where the map screen and the game screen are switched?" And well, it was intriguing enough that I stuck around to play for a bit and see what it was like: maybe you really can boil down a Metroid game just to its raw map elements and it would be just as fun.
Unfortunately, it didn't take long for the intrigue to dissipate and I was just left bored. With no sounds or music or juicy effects apart from a few token screenshakes to help the lackluster minimal graphics, the game just felt incredibly dull. Every dead end I encountered just made me dread the absolutely dreadful amount of backtracking I'd eventually have to do considering there was no fun movement or combat or anything to spice up the travel time.
So while it was an interesting experiment, unfortunately this was an experiment that didn't work for me. Graphics aren't everything and sure, if you had a Metroid game on Atari or something lowfi like it this would probably be what the game would be like, but still, I think this proves there's a good reason to have a fun character to control and an interesting world to see. Reminded me of playing Doom from the 2D map view: sure it's possible, but it's definitely not the exciting experience I want!