Half of the assistant coaches are black, that signals what's coming, same as all the black starting QBs on I-A programs signal that the process of trying to blacken that position is not about to be halted. The black coaches (and black QBs) will keep coming and coming. If some or even many fail (as has been the case with black quarterbacks) there will be many others to replace them.
Also, I don't think the owners "hang out" or identify with head coaches, nor do they need black players to "keep making money." Owners are considerably above coaches in the economic and social pecking order. Caste System logic mandates that if the players are predominantly black, then it's "racist" for quarterbacks, coaches, announcers, etc., not to be. As long as the owners, GMs, and high-ranking executives in thebusiness and related media stay overwhelmingly white, the product frombelow that levelcan be continually blackened over time.