They seem to have reappeared out of stealth mode. I wasn't aware of their rebrand.
https://mips.com/press-releases/mips-announces-availability-...
They announced ending MIPS ISA development and switching to RISC-V in March 2021:
https://www.eejournal.com/article/wait-what-mips-becomes-ris...
https://www.prnewswire.com/news-releases/wave-computing-and-...