https://www.sciencedaily.com/releases/2021/04/210430165903.htm
So, the gist of it is, Spectre was a problem discovered in 2018, and a new research team has discovered a vulnerability related to it that renders all mitigations to date null and void. Affecting both Intel and AMD processors which have micro-op caches. The research team says there's no mitigation yet, and any mitigation is likely to have a severe impact on performance, so "good luck everyone!"
All CPUs are doomed.
No, at this point, only CISC CPUs of the majority AMD x86_64 instruction set are doomed. That article says nothing about RISC CPUs, nor about any software translation employed by operating systems running on those RISC CPUs. No mention of ARM, PowerPC, or RISC-V in that article, just Intel and AMD x86_64 processors.
Which is the majority of desktops. Meaning we as consumers for any decent performant things are doomed.
I consider RISC performant enough. Was nice knowing x86 hardware, and I mean this generously, because it really wasn't nice knowing that huge hot mess of an instruction set.
True. :)
x86 was indeed a garbage fire.