Not at all.
I would say the module should be worth at minimum what you pay for it at the time you pay. Everything after that is gravy. I couldn’t put a price-tag on that.
Once you pay that money you have little real power to force further development. It’s not like you are going into contract with a home-builder with legal recourse if things don’t go as planned.
Angrily mashing away at a message board might seem a way forward, but end of day it is counter-productive. It removes value from your original purchase by creating a toxic community, and it discourages new customers from jumping onboard - thus reducing the chance that development will ever occur.
Of course some folks just don’t care and are happy to extract their value with a pound of flesh. Selfish, bassmoles IMO.
ED policy is to ban these people from their forums. I understand that perfectly. Unfortunately, the only way to identify them is by the disrespectful way they write. Sadly, this filters out many folks who may be trying to be constructive, but just don’t know how to write.
That’s a much bigger problem facing modern society. I weep for the state of education in the US and the effect of the internet on personal communication.