For me it’s Super Metroid. I have played Zero Mission, Fusion, Metroid: Samus Returns (3ds) and Metroid prime remaster, three of these games are remake/remaster. So you can see why I’m hesitant to start Super Metroid, I’m sure that game still holds up, but playing it with modern controls annd other bells and whistles would be more ideal.
Thinking about those I’ve played, I don’t think remakes have ever detracted from the original to me.
The first time I finally completed Metroid 1 was shortly after Zero Mission (which had the cool effect that the locations of some power ups was still fresh in my mind).
I also enjoyed Samus Returns despite it missing the point of Metroid 2, and that didn’t make Metroid 2 worse in retrospect.
Kind of similar with Majora’s Mask 3D, Mario 64 DS…