We don't rotate lineman other than to phase them out (*cough* Wilson *cough*), so I don't know how else apparent future early round pick Corcoran would've reduced Jaimes's snaps. I love me some Corcoran as much as the next guy, he very well could turn into a high pick but that has little bearing on how ready he is/was to take snaps from Jaimes.
I just don't think we can hide the criticism by pretending it's coming from one of the guys transferring for playing time. I don't think it's news, there were reports of guys (particularly on O) checking out when the season was initially canceled and struggling to get back into it. I'd be more shocked if he had said there wasn't anything like that, because then I don't know where that performance was coming from. It's a frustrated guy referencing problems we knew we had. Wish they had more follow up questions on how he felt about it moving forward/if those guys were still going to be problems, but it is what it is.