To be fair, I have not had the honor to be a docker customer. But regarding the kernel thing, I have limited IFY. Let's say if you goal is to keep yourself up-to-date with kernel tree, probably you have to compile the kernel DIY. The hardware dependencies and customized kernel config is not that handy. Then if you pick a distro, probably, not sure it is a problem, things like initd sneak into systemd/sysctl brought the element of surprises occasionally. While, to move or not to move, both are forwarding and backwarding.