Mandatory registration to download an ISA specification? Really?
Their registration form is also broken.
ARM did the same thing, last I checked. I have no idea who they think they’re benefiting by doing it. Lawyers and marketing, I suppose.
The people in the hardware business usually have to do NDA’s and such on top of mere registrations. If anything, this is a step up from what they’re used to. Especially if they use an open-source implementation of MIPS. My favorite being CHERI, a capability-secure version of BERI (64-bit MIPS).