Considering how most college HC's have to deal with NIL and transfer portal as being permanent relavent factors to contend with in recruiting, building up and consolidating, later on, adding and subtracting a few roster spots annually as years go bye, you might actually see more future college HC's make the leap and transition to being good NFL HC's because they'd have some experience dealing with FA or salary cap-like issues with transport portal and NIL.
And lets be honest, when it comes to NIL, who's most likely to receive these endorsements? Mostly offensive players, like star QB's, RB's or WR's. Maybe the occasional LB or big, rough-and-tumble DE types, but typically O-linemen, D-linemen, starting LB's DB's and CB's aren't the ones racking up huge endorsement deals with Subway or Academy Sports.