The thing is that whilst ME2 did make some gameplay changes to improve over 1 (which was by no means a perfect game), in many ways it just went too far. Like, yeah, the inventory interface in ME1 was abominable, no question about it. The solution was not to remove the inventory. Overheating instead of ammo was an interesting mechanic that had both lore backing and impact on gameplay, so they stripped it entirely and hey reloading like old times. etc. etc.

ME2 ended up, to me, feeling like a boring and fairly generic game that happened to be in a setting I like. ME1, for all its flaws, ended up being something I really remember, thoroughly enjoyed, and have replayed since more than once.