If we consider 'by numbers' to be the most important metric, I suspect the
8051 is still the world champ ISA. But I'm going to set 'by numbers' in
this context over here next to 30+ years of "x86 is definitely, without a
doubt, no question dead in the water Real Soon Now".
P.S. - I thought RISC-V was killing x86 these days. ARM killed it last
time. Itanium the time before that. And the RISC hoard before that.