They are not sold out. It is just a lot more work to support retail on a novel new product, so they are focused on hyperscalers and CSP's. Don't forget that high end GPUs are US export controlled as well. They are considered weapons by the government. [See 88 Fed. Reg. 73458 (Oct. 25, 2023) and the Export administration Regulations (EAR)].
Why not? Because they’re sold out to hyperscalers?