There are a ton of experienced and available managers right now who would coach circles around Gregg. Luis Enrique, Zidane, Pochettino, Roberto Martinez, Joachim Low, Rafa Benitez, Claudio Ranieri. Didier Deschamps is out of contract with the French team after this World Cup and is said to maybe want a new challenge. There are a lot of really good managers available at the moment.
Some of these guys would likely not be interested and/or cost prohibitive but why not at least try and swing big? You don’t think someone will be excited about the opportunity of leading the best team the USMNT has ever fielded in a World Cup cycle that’s ultimately hosted by the US in the first run of an expanded tournament? It’s a massive opportunity. Saying we should settle for Gregg because no one better would be interested is honestly crazy to me.