Given those models aren't sold at MSRP anymore and are primarily being sought for inference, it's apropos of an article on the costs of inference on Apple Silicon.
Not sure what you mean by "can't order", both of those links show purchasable, orderable computers with RAM upgrades. You can get the Mac Studio in 12 weeks or the MBP in just a few weeks, with RAM upgrades, by ordering right now on Apple's website.
Given those models aren't sold at MSRP anymore and are primarily being sought for inference, it's apropos of an article on the costs of inference on Apple Silicon.