ME3 wasn't significantly rushed though. The main complaints about it would not have been fixed by Bioware having more time- the ending/ Starchild was not due to not being given enough time (mostly it was a botched way of explaining important concepts to the player) and the shoehorning of MP into the war readiness (or whatever it was called) and initially not being able to reach the max level of it without playing MP (or microtransactions, presumably) wasn't a time constraint thing. K** L*** wasn't a time constraint thing, someone actually thought he'd be 'cool'.
I say it every time the subject comes up but ME2 was simply awful from a narrative perspective and the only thing which moved the story forward significantly was locked away in the last DLC. Apart from the companions 95% of ME2 might as well have not happened so far as overarching plot was concerned. That was the fundamental problem with ME3, it had to do everything plot wise and there was no practical foundation laid by the previous game. The things people complained about story wise would have been far better received if they hadn't come out of the blue but been set up previously. The 'traffic light' ending was almost identical to the end choices in Deus Ex, and they were well received there. And K** L*** was... well OK, irredeemable most likely, but at least if he'd been set up in ME2 he would not have been so jarringly awful.
A decent comparison would be Game of Thrones' last season, though it would have to be acknowledged that there was a big writing change for Bioware when Karpyshan left whereas Benioff&Weiss were constantly there. It wasn't bad because it was rushed, it was bad because the writers did a bad job setting expectations and executing what they had set up, while the more technical side and the actors were as good as ever, mostly, and delivered the best they could from the production direction given. They could have had another extra season or 4 more episodes and it would still have been rubbish, if left as written. Then again, ME3 was a pretty good game with deeply flawed aspects, mostly writing, while GoT's final season writing was a black hole of mediocrity which sucked every bit of enthusiasm for the franchise out of public consciousness.