I’m not following.
If I offfer my Antonov for $20 and make it clear you are getting exactly what you are buying and I won’t plan to update it, I won’t talk to you, I don’t plan to do anything else. Then you are free to buy it or not buy it but you can’t demand anything else.
If a dev, like Cockspur, is unfriendly to customers you are free to stop buying from them, but being a customer does not create any obligation about them being nice. I agree with you being rude to customers is very stupid but it is not only legal but also works.