I think it's reasonable. Though, we do need the Lightning Network to be implemented before Bitcoin becomes primarily a settlement layer.

Eventually, in a couple decades, the block reward will no longer provide enough incentive for minors to keep the network secure. In the long run, we are going to need much higher transaction fees (I'm guessing somewhere in the neighborhood of wire transfer fees) to keep the network robust and secure, and provide enough incentive for a large number of miners.