EXACTLY.
If you are a photographer, a developer, a graphics designer, a musician, a teacher, or whatever, and you are looking at buying a new Mac, what is going to get you to buy the new Apple Silicon powered Mac which is almost certain to impact your workflow in some way? If you are making purchase decisions for classrooms, what makes you buy 200 Macs with a new, unknown architecture?
The first generation of Macs on Apple silicon absolutely needs to have a significantly better price/ performance point versus the current generation or they won't sell to anything more than the most loyal fans. If the new Macs come out and pricing is not good, I could seriously see a sort-of anti-Osborne effect where people gravitate towards Intel based Macs (or away from Macs entirely) to avoid the risk of moving to new architecture.
If anything, I expect margins on the first couple generations of Macs to go DOWN as margins on the first couple generations on all Apple products are lower (also public record).
Yes, the "unknown" architecture powering the highest performing phones and tablets.
Apple has plenty of problems selling to schools for classroom use because other platforms have invested more in that use case. But ISA being the reason? No. Simply no.
IT managers are conservative, if they make a bad call, they have to support crap equipment for the next 5+ years or so. Yes, I'm aware Apple's CPUs are in the iPhone and iPad, but it's a huge change for the Mac and it's a big risk for people making those purchase decisions.
1. This is risky for consumers. Whereas the PPC->x86 move was clearly a benefit to consumers given how PPC was lagging Intel at the time, x86 had proven performance and a massive install base. It was low risk to consumers. This? Less so. Sure iOS devices run on ARM but now you lose x86 compatibility. Consumers need to be "compensated" for this risk. This means lower prices and/or better performance, at least in the short-to-medium term; and
1. This move is a risk for Apple. They could lose market share doing this if consumers reject the transition. They wouldn't undertake it if the rewards didn't justify the risk. They will ultimately capture more profit from this I'm sure but because of (1) I think they may well subsidize this move in the short term with more performance per $.
But I fully agree with an earlier comment here: Apple has a proven track record with chip shipments and schedules here so more vertically integrated laptop hardware is going to be a win, ultimately.