Just wait until you try the front facing camera on a MacBook (in my case, the Air from 2019). It's so horrible compared to any recent iDevice from the last years. I don't understand why they don't improve them to match the mobile quality at least.
tl;dr: phone webcams have DMA, laptop webcams are using USB.
I'd say a more likely (and harder to fix) explanation is that the phone ones can be deeper; laptop ones have to be very slim to fit.