You get a quest called race against time in ME1 and you can literally so the most inane things while the plot stands still for you. That's awful. Even DAO was awful with things like the Circle tower trip. That's the biggest problem from an RPG point of view with Bioware's open design - it undermines the very idea of RP by removing any weight from your decision. All you're left with is headcanon.
That's precisely my point... no consequence. In ME3, you could still juggle the order of the missions around quite a bit, but not without consequence. In ME1, however, you are not able to do the missions in any order you want either. For example, you could not do all of the side missions before doing any of main missions, because parts of the galaxy map don't show up until after you do Feros and other different parts don't show up until after you do Noveria. It wasn't a case of there being a consequence, it was a case of just not being able to do them until after the main question unlocked that area of the map. Still, ME1 leaves the impression with players that mission order is completely open and ME3 leaves the impression that the mission order is almost completely sequenced... while neither impression is completely accurate. Flipping the order around in ME3 actually has quite a bit of influence on the "role play" aspects of the game... moreso than the dialogue options (which I agree with everyone that there is significantly more autodialogue in ME3)... but a lot of different dialogue is triggered by simply doing the missions in a significantly different order (and accepting some of the consequences of changing up that order).
In ME3, I think Bioware wanted to move away from the strict Paragon/Renegade dialogue alignment issues that were present in ME2. Many people seem to be very afraid of straying into the middle P/R ground in ME2... which again can be freely done by the player, but comes with consequences... and the players complained about that.
ME1 allowed players to again freely "alternate" between paragon and renegade dialogue with very little consequence. In fact, one can play the game to unlock both the Paragon and the Renegade alignment quests by the end of the game (without glitching). I've intentionally done it by carefully metagaming and selecting dialogue options to maximize both the paragon and renegade points... and recording everything on a spreadsheet. In that playthrough, my second alignment quest (the Paragon one) unlocked just as I accessed the galaxy map to go to Ilos. It was the only playthrough where I point blank refused one of Hackett's requests. However, I went back into the save later and replayed it from a point just before the lockdown and did the Beseige Base quest on my way to Ilos (just to prove to myself that I could) and there were no consequences reflected (i.e. absolutely no difference in dialogue options or gameplay options) during the Ilos mission.
Having no consequences, however, detracts from "role playing" IMO... and I actually feel less able to role play in ME1 than in ME2 or even ME3; that is, in the sense of having my PC reflect the possible consequences of being of a particular type of character or making a particular choice). Yes, in ME2 and ME3 the possible consequences are posited by the developers (not the players)... but the developers are, in reality, the "directors" of the game and they need to retain that agency in order to produce a coherent story. My PC is just an actor in that story; and as Gothfather stated earlier, actors in movies have very little agency and they can still play a role (i.e. role play).
Can Bioware do more to give players more agency... probably yes; and I expect they will keep trying some different approaches to do so until they find one the players are happier with. Will we ever get complete agency? That's about as likely as actually going ot Andromeda IRL. If it comes down to a choice about sacrificing story and cinematics to give players agency, I'd prefer to keep the story and the cinematics.