So dealing with all your described is just not practical. Time is valuable. If somebody is creative and wants to provide some value, fighting with the system, preparing some documents, registrations hiring lawyers etc. is the last thing they want to and likely would rather abandon the project instead. Life is too short to deal with the bullshit.
Not to mention that even if what you said is very reasonable most developers will have no idea. It's scammers (efficient ones) that have to know something about copyright law, DMCAs and so on.
Problem is not that easy to solve. App stores can't spend too many hours on each app because there's tons of them, and if they would only invest time in helping those apps that provide enough profit to be worth it, that would create inequality and also many outrages over inevitable false positives.
That said there are of course many many things Apple could be doing better, especially given their fees. Also I wish subscription based model would just die. Should only be for cloud based services and wherever possible those should be optional. Or at least as simple thing as automatically not paying for months when you didn't open the app (with very few exceptions like storage services etc).
Btw, we should have some attribute for web that marks link as scam/negative. These tweets and HN homepage just made those scam apps easier to find.