I had emailed them 5 months ago about whether they planned such a store and whether it would be worth planning to make an app in time for the librem release, but did not hear back. This is the answer I suppose. The question is whether they plan to monetize it. I think they have to - there has o be a way for developers to pay their rent when working with free software. I hope they can pioneer something along those lines

How did the elementary app store pay off BTW? Are there any numbers available?