Quite frankly this should be an optional security feature I can flip off with a physical switch on the board - go show an alert on the BMC for all I care, but as is this is total bullshit.
IANAL; I wonder if this would be grounds for a class-action lawsuit in the future. Something like suing the motherboard manufacturers to replace every CPU their boards have broken by this method.
Expressing discontent in an open forum can catalyse a much larger reaction that PR depts will pay much more attention to compared to a few angry emails or twitter DMs.
If you don't want a platform-secured CPU, don't buy one.
As Chris mentioned, this is exactly what Big Corp™ wants. They'll be the ones buying it too, and would likely pay extra for such a feature. They're the target market for these vendors.
Thus, sure, for those looking to buy second hand, this is indeed advertising irreparable damage. But for Big Corp™, this is advertising security (in my opinion quite rightly so), and ensuring their data isn't stolen.
Admittedly it feels like AMD could have created something that allows the chip to be reset providing you have the original signing keys.
...the problem is what happens when you buy an unlocked CPU.
So, the server maker then owes me a new cpu (of the same model obviously) that does work.
It'll be interesting to see the legal fallout from this, as purposely breaking customer owned gear is not going to end well.