Edmure absolutely deserved to get crap

his entire speech was entire BS and was a demonstration of how out of touch he was

1) He royally screwed but Robb Stark's plan to pull the Lannister's army out from Harrenhal back into the West so that he could either win in open combat or slip past it and get back east. You could argue this led to Robb's death because he had to escape north. If he can get the Lannister army in the west and be it. Roose Bolton probably doesn't betray him because Robb would have been in a position of strength. He likely can take boats north to retake winterfell instead of going over the Twins

2) He couldn't hit his father's funeral boat.
3) His actions to turn over Riverrun resulted in his uncles death. He essentially betrays his family for being a stooge of the Lannisters.
4) He did nothing in the Great War nor Dany's war to take KL.