That's fine, but for me, it stops being x86 if it can't run legacy code. A 64-bit only CPU may be a sensible thing, and we can use emulators for old stuff, but

That's fine, but for me, it stops being x86 if it can't run legacy code. A 64-bit only CPU may be a sensible thing, and we can use emulators for old stuff, but when we are at it, do we really need x86 at all? If we are to break compatibility, couldn't we just switch to ARM, RISC-V, or something else? I mean, that's what Apple do, they did it successfully, and more than once (68k, PPC, x86, ARM), but Apple is Apple, and x86 is (was?) all about backwards compatibility.