It's kind of strange how this is the highest rated game of all time, yet still manages to often be undercredited. I think a lot of people I come across now don't realize how much of the groundwork this laid for 3D action games as a whole; Devil May Cry is essentially a Z-Targeting game, Souls combat is basically 3D Zelda (except worse, lacking the creative interactions OoT offers through item usage), etc
Every time I replay this and expect that maybe my opinion of it would be weathered by time, I always find that contrarily, the older I get the more I appreciate it. Gameplay, presentation, and story are all great.

Samus' controls are improved from the first game and a number of series mainstays would make their first appearances here (this game is not given the credit it deserves by Metroid fans)
Biggest problem is the lack of visual variety which can make backtracking confusing. I played it with only the official GBC palette for authenticity, but there's a colorization romhack out there that looks good and gives it different color palettes for different areas. Highly recommended, in hindsight I wish I used it.

A product of its time, for sure, but a fulfilling experience nonetheless and one that doesn't seem to be properly appreciated among zoomers. As far back as 1986 Metroid is a very inventive and genre-defining game and while some aspects of it could certainly use work the core gameplay loop is timeless and would later be refined to the point of spawning an entire genre. I'll add that a lot of younger players seem to have missed the point; the lack of a map and hostile, unpredictable world are an integral part of the experience. Samus is entering uncharted, alien, enemy territory. To enjoy this game you need to understand that part of the concept is familiarizing yourself with and mapping out Zebes with deliberacy, and being a Famicom-era game it won't hold your hand.

I really, really wanted to like this game, and there are things to like. Its combat system is very robust and at a high, technical level offers a lot of depth. But the stuff you can do if you lab the game daily and play with a claw grip just doesn't absolve this game of its massive flaws in level design and in enemy design (which ends up detracting from what would otherwise be an extremely satisfying combat system)
There was so much potential, and also so much realized potential in the possibilities of its combat system, that I feel bad giving this game a 6/10 but I find it hard to rate it higher while still being honest about the game as a whole.