We might see more athlete-type QBs who can play a slash and run the wildcat or the option in the red zone being recruited. Maybe, if you get an arm one year, the next year you focus on a running QB..
I think you'll just a premium on
1. 4 and 5 star Fr and RS Fr. Those guys will more likely be willing to sit for a year or two, but not more. Your backup is going to be young at top programs.
2. Just paying guys a lot, including maybe even paying backup QBs to come in, ie, OSU has their star in Straub, has a true FR who is willing to sit for one year, and brings in a grad transfer G5 kid who has already played a lot of football and is willing to sit on the bench for $150k as a veteran backup. Really, I think this is one option for the elite teams, who are going to be the one most impacted by this since they're the ones recruiting and sitting a never ending chain of 5 star QBs.
3. 2-3 star guys who will be somewhat more willing to sit around at P5 programs. There won't be the big money at smaller programs, so if you're not a mega stud who can start anywhere in the P5, it may still make sense to hang out where you're at and make a decision before your last two years of eligibility or so. Being a development guy at a middling P5 school will likely be better paying than starting in the FCS. This is more likely the class of your middle tier schools like NU sit.
The fourth option is just teams don't have backups and suck when their starters get hurt... which, let's be honest, everybody but the elite teams suffer from anyway.