Let me offer another angle; nobody has to agree, but just consider ...
When Solich was let go, TO was out-of-his-mind pissed off. Go back to his comments at the time -- they were strong and critical. To a lesser extent, you could tell by his comments that he disagreed with Bo's dismissal too.
When I read these comments regarding Frost, they strike me as pretty tame in comparison. It is noteworthy to me that he never even suggests that Frost should have been retained. TO threw him a little bit of a bone with the "bounces" and "good person" comments but, really, what do you expect him to say about the QB who led his team to a national title?
My take on these comments is that TO knew Frost had to be fired. Notice that TO does not take issue with Trev and offers no alternative by which Frost could have been retained. TO knew it was time. He found something nice to say about Frost on his way out. It's what TO DIDN'T say that I find revealing.