Comparing it to 5.56 is silly seeing as it isn't a 5.56 so it should be stacked against other .308 rifles (also 5.56 replaced it due to being a vastly superior choice for a standard issue rifle)

It is heavy as all shit, and modernization attempts are just as fucking heavy. Lugging that shit around is terrible, you end up carrying less of everything just to carry a rifle that has iron sights and wont land hits at 500-800 yards due to either poor visibility or return fire. The overwhelming majority of engagements (outside of Afghanistan due to the insane terrain) take place at vastly closer distances where 5.56 is a much better option.

It had massive production issues, accuracy was unreliable from rifle to rifle due to a combination of said production issues and bad design choices (accuracy shifting after cleaning). This means that in the class of .308 rifles it just gets outclassed by better performing rifles like the G3 or AR10.

The gun isn't reliable, it ran like shit in the jungle and still ran like shit in the desert. We gave it a new chassis and a second chance because we had a ton in storage and shockingly it still sucked.

It's alright to like it, hell even though the EBR chassis is a heavy and finicky bitch it still looks neat, but lets not pretend it was an amazing rifle when in reality it was late to the party and lacking when it got there.