The claims that they had 5000 or were making a loss were rumours dismissed by AMD, but given this is the first 7nm product with buckets of HBM I don't think anyones expecting there to be a steady or cheap supply anytime soon so there's probably a good amount of truth in the rumours. Though of course, this die has been in shipping enterprise products since around November and this is the cut down version of the die, with the 64CU version of Vega20 being enterprise only (so far), so it's not like it's a rush from the assembly line or anything like that, just classic old yield issues presumably, those interposers are easy to f* up.