I'm quite thankful for the Qemu and Buildx Github Actions. I'll build and test my docker image locally as I want, and then use Github Actions to build for multiple platforms and publish. So it saves me a bunch of hassle. I usually go for:

--platform linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64/v8,linux/ppc64le,linux/s390x

Which seems to cover most cases including Raspberry Pis.