Blog post: Some ideas on what Linux distributions can do about the new kernel situation https://utcc.utoronto.ca/~cks/space/blog/linux/DistributionKernelHandling2024
tl;dr: distributions can longer release whenever they want, have the same kernel version for years and years, and have great security (unless they want to do a lot of work themselves). But realistically they never could.
Volunteer run distributions should probably get used to updating their kernel versions over the lifetime of a release. Commercial ones? Whatever you'll pay for.