Did you actually look at the ratings and reviews for that $125 audio editor?
https://twitter.com/lapcatsoftware/status/151368423425011713...
https://apps.apple.com/us/app/audio-editor-record-edit/id115...
https://twitter.com/lapcatsoftware/status/151368423425011713...
https://apps.apple.com/us/app/audio-editor-record-edit/id115...
Again, the fundamental question at the root of this issue is who's to decide what things should cost? Since when is it illegal to offer bad products that cost too much? That's a negotiation between creator and potential customer. Not buying a product that doesn't meet your expectations or budget is perfectly fine. This doesn't need to be regulated.
The regulation is that an egregiously bad app should not be allowed to be present on a top grossing list. Apple should inspect this case and allow dissatisfied customers to receive refunds accordingly and swiftly.