Maybe the support isn't worth paying for
Is it maybe possible that if no-one wants to pay for your support maybe it just isn't good enough? There's plenty of projects where the support is excellent and well worth it but also plenty where it's either worthless or just far too expensive for what it is. Especially when more than one person offers support.
If you want to be a commercial operation you need to provide commercial levels of service. Not suddenly decide you want to try to take your toys home because you think your one man band can charge like Oracle on a perpetual basis and others disagree.
You'd think all maintainers were saints from the way some of them talk. Some are. Others are bloody useless, and will leave all sorts of problems (and submitted fixes) hanging while they pursue whatever their current interest is without letting anyone else contribute.
There are projects that are basically baseline functionality these days & embedded everywhere where the concept is good, the support (commercial & otherwise) plentiful yet you still have core maintainers who basically refuse to maintain beyond their current pet feature, and when you start poking you find that what looks superficially well designed & documented with plenty of testing is actually a mess where the features don't work and the tests don't test. And when the bugs (and fixes) go in they'll sit forever ignored...
No one makes you do these projects and if you don't want to then fine. But don't scream because you went in trying to look altruistic and the cash you actually wanted didn't roll in. If you wanted money then choose a commercial model from the start instead of moaning that the grasping bastards aren't charitable enough.