Again, he's bigger and probably more talented than Bennett. But let's not automatically discount Bennett's chances. Was he deemed good enough to be the future? No. But, how many 5'11" 190 lbs. QBs get that opportunity?
Though he may have been running the scout team during the season, Bennett has had the playbook(s), been in the QB room, and will still be working with the offense(s) in OTAs through for his 4th NFL offseason before we even get to this upcoming (and his 4th) training camp. How is that not advantage?
And again, Simpson's initial learning on the job might affect the training of the others on offense of a team ready to go now. These guys have to be able to communicate McVay's long winded play calls, master the QB cadence (instead of just clapping their hands for the snap), possibly assist in line calls, etc.
Sorry, but while I was very early on the Ty Simpson bandwagon, I'm not going to totally disregard Bennett who has shown steady improvement in the last 3 preseasons. And it's possible that could continue this year if given the opportunity.