That seems like a false dichotomy. Anyway, it's unprovable either true or false, because no evidence exists.
Let's just assert that it's false, then. Let's say 30% is unreasonable, and that iPhones would be as successful even with yet more unreasonable developer fees.
Would the iPhone be as successful if it took a 99% cut and nobody would bother developing paid apps for it? Probably not. Whether 30% is the sweet spot is unclear, but given that there is plenty of paid apps on the platform, why would it be unreasonable?
