Re: Advanced Kernel
I have heard elsewhere that SuSE maintains its own set of custom backport patches for btrfs, since it is used as the root fileystem within their main distribution.
Oracle at one point actually distributed tools that would format btrfs with advanced hashes (sha256, xxhash, etc.), but their UEK didn't have the driver support for anything but crc32c - I don't think SuSE would have shipped anything so disjoint.
I'm assuming that Rocky doesn't really bring anything to the table from this perspective - they just rpm-rebuild whatever RedHat shipped. If Oracle and SuSE pooled their efforts, then I think the result would offer great advantages over stock rhel.
In the 90s, IBM/DEC/HP used POSIX to seize control of UNIX from AT&T and Sun. OpenELA would be able to do the same to IBM, if the advantages were compelling.