Professional PC productivity software sells just fine
Console games sell just fine
It's only web and mobile where this becomes a problem, so why is that? The web I understand because it started out free, the App Store certainly didn't though.
Professionals actually buy based on features and what they need, not what looks entertaining.
Ditto for console gamers. It's a more informed audience that's concentrated in a small group of people with far more disposable income than a regular smartphone user.
Apps are a victim of regular people's expectations. They aren't used to paying hundreds for Photoshop. They're used to everything being free. Apple certainly hasn't helped developers in this regard, as it's encouraged commoditization of apps through its inaction against the proliferation of free-to-play and the race to the bottom.
Console games sell just fine
It's only web and mobile where this becomes a problem, so why is that? The web I understand because it started out free, the App Store certainly didn't though.