There is a subtle difference between "I would like to know when this will happen so I can make plans"and "I need this done because I'm being paid for your work, please hurry". If the requester left out the background information, the tone of the request would have been more of the former and less of the latter.
I disagree that this would have been the right thing to do. There's nothing wrong with explaining why something could be useful in an open source project - if the reason seems like something important that a lot of other users of the software would also need, the maintainers of the software might want to know about it so that they can add the feature or fix the bug sooner. It can also help if there's some way of working around the problem.
Calling the developer extortionate was unreasonable, but I don't think there's anything wrong with the first message.
