So depending on product category it might be a large drop (EU study finds -38% displacement rate for books) but it might also be a boost (EU study finds +24% for video games), and it is hard to say in general, since even a 90% piracy rate might only mean a maximum of 5%-10% lost sales (from the wolfire blog post). Either way it isn't at the level of "impossible to succeed".
If we are talking about app stores specifically, I bet a much bigger factor in (lack of) success is discoverability, both because your app is literally hard to find and because app store owners allow a flow of cheap clones to compete with your genuine app.
So depending on product category it might be a large drop (EU study finds -38% displacement rate for books) but it might also be a boost (EU study finds +24% for video games), and it is hard to say in general, since even a 90% piracy rate might only mean a maximum of 5%-10% lost sales (from the wolfire blog post). Either way it isn't at the level of "impossible to succeed".
If we are talking about app stores specifically, I bet a much bigger factor in (lack of) success is discoverability, both because your app is literally hard to find and because app store owners allow a flow of cheap clones to compete with your genuine app.