Do any of the major Linux distributions (Fedora, Debian, Arch, Ubuntu, etc.) provide timely security updates for the
aarch64 architecture for kernel and other standard system components present in a default 'desktop' install (I'll define that as the 'most standard install' that will run a web browser)? Have any of the relevant security teams indicated any (informal) commitment to ongoing and timely updates?
I ask in the context of SBC (single board computers), in particular Raspberry Pi 3.
As an example of the possible shortcomings I have in mind, this post indicates that security updates in Raspbian back in 2013 were sometimes unavailable (and in fact I believe I read elsewhere from a Raspbian maintainer that their kernel updates in particular were not always as timely as for other system components, because of the modifications made by the Raspbian team).