What’s not clear to the customer is what kind of support you’re getting with the price. I’m not sure if it would make a difference but, for a professional, knowing in advance that you’ll get good support may motivate one to pay for the higher priced app.
I few years ago I purchased Teleprompt+ from BombingBrains, an indie developer, for my iPad teleprompter.
At about $25 it’s priced a bit higher than the bottom feeder iOS prompters.
https://www.bombingbrain.com/teleprompt.html
They even had a page on their site explaining that they were available for hire. Truly a mark of indie developers who knew their apps weren’t a sole source of income.
When I had questions/issues with setup and functions, they were quick to respond. Almost always within 24 hours and it was one of the developers, not a “support” person who responded. After a few bug fix updates things went silent for a long time. One day I searched to see what had happened and I discovered they had updated their app, which requires a new purchase.
I don’t have an issue with complete new purchases in that price range. There’s no upgrade pricing in the App Store and, given the value, the full price is really no more and probably far less then the upgrade price of a professional app.
What surprised me though is that I never received notice that a new version had been developed. Given past correspondence they certainly had email contact info for me. Had I not checked I’d have assumed (and actually had assumed) that they abandoned their apps. There’s also no notification in app that lets the user know a new paid version is available.
I do think if Apple allowed upgrade pricing they wouldn’t drive developers into bottom feed pricing structures. It doesn’t help that apparently there’s no in app notification of new versions.
Support absolutely costs money but, whether it’s the app store rules or the companies, if you can’t exploit your current customers whether it’s paid upgrades or even new paid versions, you’re being pushed into a model which doesn’t motivate support from the developer.