I mean are we really arguing that Lem is some good coach at this point? No good coach fields teams back to back that are this bad this deep into their tenure. None.
This was an interesting point, so I went and looked it up. A couple have been pretty bad (Van Horn went 26-29), but I haven't found one back to back yet. And certainly not after a national title, i.e. you're 'established'. Jon Savage at UCLA is the only one who comes close, they went 25-30-1 after they beat us in 2013, then rose up to a national seed the following year, fell off and went 25-31 the next, went 30-27 the next year then finally got back semi-permanently. But they haven't become elite again yet.
ETA: Guess you could add Ron Polk. He didn't technically do it, but had he stayed in 2009, he knew his *** was headed for it. Augie Garrido same boat, but these guys were old.
ETAA: Andy Lopez at Arizona dropped a little bit, but didn't technically have the 2nd losing season. Then Jay Johnson nearly won it all with his players in 2016 after he retired. Another is Mike Batesole at Fresno State, he left last year after 2 in a row. But again, at the end of the career.