Right but what happens when another blockchain technology hits the scene that’s trendy and happens to be PoW? People who made significant investments into GPU miners and the infrastructure to support them won’t go away quietly.
That's fair, what if another PoW coin gets really popular?
The good news here may be two-fold
1) the existing group of public chains have matured greatly and their network effects are quite strong now. It is no longer so easy to start a new chain
2) virtually all new chains are PoS because it's understood to be significantly more secure and less expensive vs. PoW
3) public chains take years to grow, and right now, there is no PoW public chain on my radar that has a chance of generating nearly as much mining demand as Ethereum (and Bitcoin but ASICs)
For those reasons, the idea of a new public chain appearing from nowhere and impacting GPU demand seems in practice unlikely to occur.
> virtually all new chains are PoS because it's understood to be significantly more secure and less expensive vs. PoW
PoS security relies on the integrity of the stake — and the integrity of the stake relies on the “security” of the PoS system. It’s an intractible circularity problem.
Yes, a large sample of recent altcoins have shipped PoS, but this is no more relevant to a PoW v PoS security debate than a modern top 40 “hit songs” chart is to a debate over Beethoven v Bach.
