Valestein
Arcane
The Protheans were finished the moment the Reapers came through the citadel and wiped out the seat of power for their empire and took control of the relays(a plot point ME3 conveniently ignores in several ways). It was made clear by the Prothean VI in ME1 that their "war" against the Reapers involved isolated worlds being picked off one by one. That they were somehow "close to stopping the Reapers" is just retconned nonsense.
Then there's other issues with the crucible such as why does Shepard need a cipher to understand a simple Prothean warning but any idiot and their mother can understand the crucible plans? How come the Reapers haven't destroyed all traces of this thing that has been worked on for millions of years by different races?
There's so many things wrong with ME3's plot that I couldn't list them all in one sitting no matter how hard I tried.
Then there's other issues with the crucible such as why does Shepard need a cipher to understand a simple Prothean warning but any idiot and their mother can understand the crucible plans? How come the Reapers haven't destroyed all traces of this thing that has been worked on for millions of years by different races?
There's so many things wrong with ME3's plot that I couldn't list them all in one sitting no matter how hard I tried.