When we discuss increasing the block size, the debate often revolves around the opposing forces of network scalability and network decentralization. Big blocks will require lots of bandwidth and other system resources to make it hard for your average home user to operate a full node, the argument goes. We also hear about how small time miners with low bandwidth could get attacked by big high bandwidth miners by creating artificially large (but valid) blocks to force small time miners to download them, increasing their orphan rate.

These issues are important (although I think they are often exaggerated, see math on node bandwidth here and a large Chinese pool’s bandwidth here). But they involve a lot of assumptions and a lot of unknowns so are very hard to predict into the future. So I will not focus on them in this article, instead I will focus on what is known, the block reward. Blockchain security — that is maintaining a thriving and competitive environment to keep mining decentralized — is in my opinion, far more important than either node centralization or scalability.