> This is completely the opposite of how B2B sales work, where it is not uncommon for some development cycles to be dictated directly by a few (or even one) customer.

Development and sales (and support). Look at how many SKUs competing laptop manufacturers have because enterprises will specify some combination of ports and memory and CPU, and if the manufacturer doesn't have that particular combination, there will be no sale.

(Having said that: it's not obvious to me whether this is still as much of an issue as it used to be.)