I think there would be no "long run" for Feedly if people didn't buy Feedly Pro.
I don't think it makes sense to talk about dark UX when it comes to ads. The only good UX for ads is no ads, so there is no way to ever have a concession between an ad-supported business model and users who feel entitled to free internet stuff.
Think of it another way: someone who doesn't think your product is worth 6 dollars a month is going to be mildly annoyed by all the ads you placed.
I don't think it makes sense to talk about dark UX when it comes to ads. The only good UX for ads is no ads, so there is no way to ever have a concession between an ad-supported business model and users who feel entitled to free internet stuff.
Think of it another way: someone who doesn't think your product is worth 6 dollars a month is going to be mildly annoyed by all the ads you placed.