Just a reminder that there exist a few proposals that would fix this, applicable to all coins.
@Avivz78 and colleagues have another worthy proposal.
And EIP-1559 proposes another, more miner driven approach.
hackingdistributed.com/2019/01/22/doi…
But worst of all, they don't buy security. If miners can't predict fee income - and infrequent spikes can't be -- they can't invest based on it.