I only see bullshit excuses and greed also. Plenty other ways to make money, plenty of other ways to finish. I recall seeing somewhere that BB was bringing in 20k+ per month at some point (for how long?), which is more than enough funding to both finish BB and start another game. In fact, it's more money than most people could wish to earn, and people on Patreon do a lot more with a lot less. There is no reason to have to use Patreon, or to only use Patreon, it's possible to have one game in one location and another elsewhere, and continue to get money for both. It's certainly possible to change them all to "roommates" and just continue to story, and let the community make an incest patch. So you give away the last version, hoping to placate the community and appear selfless, when the opposite is true; sure it will work for a little while, until people are done with it and want the next load of content. It's also possible to simply finish a project, because you feel you owe it to a community and earned enough for it already.
I suspect what will happen, is the community will take over, as they have started to already, by adding new story arcs, and maybe the popularity will remain, but without DS involved.