Not sure why getting downvoted. Is this an ignorant question? Or maybe just not fans of the word agile? Oh well. Guess I’ll just have to ask someone who contributes the the kernel in person the next time I meet one.
It's a pretty ignorant question; it could also be taken as flamebait trying to start up an agile vs waterfall argument.
New stable kernel branches are released every 2-3 months after weekly release candidates, with bugfix releases in between new stable branches and a new LTS branch every year or so. If you want anything "more agile" than that for OS kernel development, then you're probably prioritizing agile dogma over the realities of trying to not break the most fundamental component of the operating system.
It sounds like you're just not accustomed to paying attention to a project with such broad scope. Most of these changes have fairly narrow impact on just a single driver or subsystem. It would be silly to say "we're going to postpone release of this new GPU driver because we have too many new network drivers in this release", because there's no reason to expect such a policy to actually improve the quality of kernel releases, and it would obviously be detrimental to the pace of feature additions.
Actual far-reaching systemic changes are a pretty small portion of this and most other stable kernel releases.
