It is also in interest of developers. Stable LTS release is good, when you want to start using something new for you without checking all bug reports first. Especially if this software intended to do something really serious and not just for game playing.
I would not mix terms “released” and “got useful”. My migration to 2.4 is quite well documented here: Migration from 1.8 to newest(stable) OpenHAB release
It was August 2019 - and 2.4 was latest stable release at that time and I still had to use 1.X MQTT binding. Not sure if it’s better now.
Nevertheless I don’t ask supporters to donate their time for free. There is an Openhab Foundation to which at least I donate some money every month as long as I use OpenHAB. I thought one of the tasks of the Foundation is to maintain release binaries, as providedhere in third bullet point. But it looks like that this goal is forgotten together with bintray.com link…