I wouldn't look down on Kevin O'Connell because he lost to Sean McVay. McVay is a HOF coach. O'Connell may well be on his way too. And you're right, there may not be a better head coach available. But we won't know unless we try. We know exactly what we're getting with McCarthy, a team that can make the playoffs and head to the couch after 1, maybe 2 games at most. A coach who reportedly quit on his team and has a history of players wanting him gone. A coach who has proven that he can't hang with the big boy coaches, and always gets out coached by em.
I'd rather swing for the fence and take an unknown coach, giving him a few years to build his team, learn and improve. Someone promising that has proven they can out coach opposition consistently.