Looks a little mean of Apple
It does seem that Apple are being a little mean. The kit was only offered to certain developers presumably developers who are important to them in some way. It is in Apple’s interest that there is software targeted for the new hardware available as early as possible. So, you think that Apple would want to keep these developers sweet and reward their early support of the new hardware.
At the minimum I would have thought $500 (rental cost) off the price of the new M1 Mac. Redeemable for a period that will cover more than just the first-generation of Apple Silicon devices. Because these developers will have probably already purchased the first-generation by now.