I think this should be the real tutorial here. The amount of flexibility that Yocto brings is huge compared to anything else you can do from any other distribution.
what's the usage of memory/storage comparing to buildroot for similar functionalities? I would expect something like 10x larger but I never measured it.
https://buildroot.org build the whole Linux system from source
https://gokrazy.org pure-Go userland for your Raspberry Pi 3/4 appliances