This strikes me as being the substantive issue. We can play "which game is more incoherent" forever -- obviously the later games are handicapped a little there because they have more stuff to fail at, but it's still fun.
But it's pretty obvious that this isn't what the debate is really about.
So, why did you feel kicked in the nuts?
Do you honestly want me to reiterate all the reasons why the ending was gruesome and felt like a betrayal? Were you here in 2012 and 2013? Did you miss all the hour-long videos people posted on youtube, the 70 000 bucks charity and the sending of cupcakes? And the bajilion posts people have made about this whole issue?
Yeah making all the previous races from all the previous cycles dumb; that would've made for a great story.
Except for one, small thing that makes the situation different this time around... What was it... Oh, how about the fact that Shepard STOPPED the Reapers in ME1!
What did (s)he stop them from? Well, from springing the Citadel trap. And now they have to come to Milky Way manually, via FTL.
We know (from Vigil) that Reapers take control of Mass Relays when they come through the Citadel.
We know (from that same source) that they use military and census data to help them hunt down the races of each cycle.
What does that tell us?
It tells us that the Reapers in all probability shut down the Relay network and then take each star system one by one, without any possibility of someone sending reinforcements or even coordinating defense. This time around we have early warning and the situation is completely different.
And you want an example?
In the 10 hours orso we fly from Eden Prime to the Citadel, Tali does the following:
-accidentally run into a Geth that heard Saren's conversation after Eden Prime and managed to steal it's memory core. This in itself is impossible (for obvious reason, I might hope), but...
-she also goes into hiding for a week orso (!)
-makes a deal with Fist.
And I got a feeling I'm forgetting something here.
Okay, so there is a minor timing issue with the initial investigation on Saren. Yes, when you dig into it, there's something off. But does it disrupt the flow of the game? No. And it's not even a lore inconsistency.
Another example is Joker - how did he get to the Citadel when Sovereign attacks, since last time we saw him he was over Ilos? Makes sense? Maybe not. Does it make you go "f**k this game!"? No.