Okay, I will assume that the government is either caring, doesn't care or incompetent (meaning not actively suppressing this). You forgot the mining side, so how do you solve that? Because, for example, the 50%+1 problem is still there, right, so if you really want a decentralised system, you also need to solve this.

Also, your solution doesn't work against oppressive governments. (Again, I don't have a solution to that, just pointing out that they do exist.)