Any ARM CPU that Apple uses in Macs will almost certainly be 64 bit A64 only - A64 is the only instruction set that has been supported on Apple SoC's since the

Any ARM CPU that Apple uses in Macs will almost certainly be 64 bit A64 only - A64 is the only instruction set that has been supported on Apple SoC's since the A11 in 2017. A64 is part of ARMv8 which was announced in October 2011 and was a brand new instruction set. It is not compatible with legacy 32 bit ARM applications and doesn't carry the relevant technical debt. RISC-V was announced in 2010. It may have many admirable qualities but claiming that it has the advantage of a newer architecture is not correct in this context. Incidentally, I think one of the remarkable features of ARM's recent commercial success - generally completely unremarked on - is how they have, relatively seamlessly, switched users from legacy 32 bit to an new 64 instruction set.