I agree that no one knows how long BTC will continue to rise, but I think the growth will continue for a long time considering it's scarcity and popularity. I think the price growth and volatility would slowly taper to a much more stable scenario over time, but when that stability will be reached is hard to say. Over time as we continue to watch the S2F model continue to play out, maybe we will begin to be able to make some accurate predictions at some point.
The problem with S2F is if you apply it to say NXT token, nXT should be worth infinity because it was an instamine and then there was no more coins issued. You probably never heard of NXT token and why would you have when its been horizontal in price for the last three years after a huge spike.
I think due to the recognition around the world, its acceptance, and a that it is the easiest crypto to trade into, creates a real use case for transferring, trading and payments. Then the limiting supply doesn't hurt.
Then there is all of the standard features such as they cannot be confiscated, cannot be frozen, you don't need a government id.
There is real adoption of Ethereum and Dash. Bitcoin Cash is getting spread out more than Bitcoin and now has more transaction volume than Bitcoin. Ether has marketcap because its a casino blockchain. Bitcoin's value against fiat is partly due to how much the fiat usecase has been hurt by financial institutions. With every confiscation (bailins), or excessive money printing Bitcoin goes up. With new financial controls, bitcoin goes up.
Could we get Proof of Brain to become something people actively use to buy services? I want to make a 10,000 POB pizza.
I remember NXT. Yeah I agree, I don't think you can apply S2F unless you have the popularity that BTC has had. I think POB will definitely be actively used with no fees and 3 second transactions. One thing I'm considering is reaching out to @thelogicaldude to set up a POB store.