It's nice for a C simulator to avoid condition codes. It's not so nice if you want consistent overflow checks (e.g., for automatically overflowing from fixnums to bignums).

Even with XNOR (which isn't even part of RVA23, if I recall correctly), the sequence for doing an overflow check is quite messy. On AArch64 and x86-64, it's just the operation followed by a conditional jump: https://godbolt.org/z/968Eb1dh1