McD should definitely be in consideration, and may even win depending on how the rest of the season unfolds.
However, it’s understandable how he’s not getting the national attention yet. As others have said, he’s got Josh and a perennial playoff team. Tomlin’s Steelers were expected to finally miss the playoffs this year. He’s got to be a favourite. Same with O’Connoll. Weren’t we all excited having the Vikings 2nd round pick, expecting it to be an early 2nd rounder?
Coach of the year is usually a measure of how your team performs above expectations. McD has certainly done that, but maybe not to the same degree as Tomlin or O’Connell (because the bar was already high even if this was to be a “rebuild year”).