That out of the way, you're right that some niches require a lot longer cycles, but it's the big big biiiig advantage of FOSS. Downstream can maintain it for as long as they wish. As you said things got shaken out by the community for free basically, and if some serious software is so so serious that upgrading and retesting/certifying is somehow more expensive than trying to airgap an EOLed pile of libs (while at the same time it needs support) then the stakeholders can do it.
