Yeah, if I'm understanding this correctly they just show that the part of the Foreshadow attack that loaded kernel memory contents into cache prior to leaking i

Yeah, if I'm understanding this correctly they just show that the part of the Foreshadow attack that loaded kernel memory contents into cache prior to leaking it, rather than working in some obscure Intel-specific way as previously thought, is actually just a known Spectre variant which works on a whole bunch of processors including AMD and ARM ones. It's not massively useful on those processors because the stage that actually leaks the memory contents and known alternatives like Meltdown are Intel-specific, so it requires a certain amount of cleverness to even detect that it's happening, but it does happen.