(I cheated a bit and used the total size of the binary, as binutils isn't available out of the box in the ubuntu container. But it shouldn't be too different from text+bss+data.)
$ podman run --platform=linux/amd64 ubuntu:latest ls -l /usr/bin | awk '{sum += $5} END {print sum}'
22629493
$ podman run --platform=linux/arm64 ubuntu:latest ls -l /usr/bin | awk '{sum += $5} END {print sum}'
29173962
$ podman run --platform=linux/riscv64 ubuntu:latest ls -l /usr/bin | awk '{sum += $5} END {print sum}'
22677127
One can see that amd64 and riscv64 are actually very close, with in fact a slight edge to amd64. Both are far ahead of arm64 though.