Given that IBM just announced a dual-ISA mainframe with support for both z/arch and ARM, they might indeed be looking to sunset POWER.

Yep, I have said it for a good 20 years now.

POWER/PowerPC is what happens when you take a brilliant design to execute it poorly. x86 is when you take a poor design and execute is brilliantly.

Dunno, I think Risc-V's simplicity gave it the initial popularity rush rather than being from a certain institution (the institution perhaps gave it visibility, but it does have own merits and no idea if other archs from the time had those?), don't remembere exactly but iirc it was possible to implement with a ridiculously small amount of FPGA gates. Conversly heard some rumblings that it had parts t hat were unsuitable for scaling up but it seems to have gained enough momentum for people to engineer past stuff like that.

About 25 years back here in Australia they were advertising Fujitsu air-conditioners, they had the promise of some like "They will get the air down to 17c in all conditions."

About a month later there was a summer heat wave and I went to a friends house who had just bought one. It was wild walking in from a 45c day into, as advertised, a 17c house. Had to give it to them, they lived up to the claim.

That they come from the telecom/server space, it makes sense they had a good eye for aircon engineering.