There's a thread that's 5 years old or so that i really wanted to necro but fought the urge.
Simply put, ME1 is the best Mass Effect game, conceptually. The problem is that actually playing Mass Effect 1 is an infuriating exercise in insanity. I first played through on PC and so the only issues I encountered were with the actual game itself, but I started a playthrough on Xbox One to get the achievements and just ugh, I hate this game
The Mako is so fucking terrible. It's just fucking awful. There is no consistency whatsoever to the control scheme and it's entirely dependent on camera. I've literally gotten stuck for a solid 30 seconds of not being able to move in any useful way. The repair function also literally doesn't work. I have repair charges. I mash Y, nothing repairs. I mean I've literally died on the lava planet trying to get to Liara like 10 times today and only one of them was outside the Mako. And these issues existed in the PC version too, don't get me wrong. The only issue that didn't exist on PC was the poor framerate, as the game obviously runs fine with all 4k texture mods and graphics overhauls.
The auto-save system is so incompetent. It will save every time you switch areas in say, the Citadel, but not only will it not autosave when you pass checkpoints in that same lava level, but it won't even let you manually save until right before you fight a bunch of Geth on foot. And that certainly isn't the only instance of it being trash. As others have mentioned before, it also runs like complete turd on Xbox. I think the problem is that this game was designed for PC and they didn't bother turning anything down, instead just porting it to Xbox originally. I fear to see the other titles on console.
There's also the fact that the combat is totally incompetent and you spend a lot of the early game with your party members flat out dying, regardless of their equipment or skills or biotics or upgrades. Usually short before you die as well.
Mass Effect 1 is still the best, despite all those issues, as it actually had an illusion of exploration and freedom. ME2 and 3 force you into pre-defined levels at all points in the game where you can't explore anything and are also being attacked by 30000 enemies which prevents you from exploring even if you could. But ME2 definitely fixed the combat issues in all ways.