While I can agree with most of what you said,
they're not actually paying for a product, they're paying to support an artist.
Just because you throw money in the hat doesn't entitle you to make demands.
Having said that he's clearly in way over his head, even before his health issues.
I still don't get why he gives himself these self imposed deadlines on updates.
Most devs just give a percentage update and only post a date when they know they can deliver.
Frankly, if at this point you still get upset at his antics I'mma call that a you problem.
I see where you are trying to come from, but your argument doesnt hold water.
People are paying to support an artist, or in this case a dev, yes. However, if the developer doesnt meet expectations, or starts making a product that people do not like, then that developer runs the risk of losing their audience. It has happened several times before (coughcoughicstorcoughcough). Its the same idea as the famous saying "don't bite the hand that feeds you". Asking someone to do the bare minimum as a developer, and communicate with their audience, deliver updates when they say they are going to, and not be an asshole is not a "demand".
I do absolutely agree that he needs to stop giving deadlines that he cannot meet. I, and a lot of people here, understand that delays happen due to unforseen circumstances. With Botn, these circumstances are constant.
Finally, at this point I am not even really bothered by not getting the update. If anything I am more pissed that Beggar had the audacity to put censored sex scenes in the files as a middle finger to his audience. To this day, I have not seen an adult developer disrespect their audience in the way that he has.