Why Is a High Transaction Throughput Challenging for PoW Networks?

A high transaction throughput is challenging for Proof-of-Work networks due to the trade-off with decentralization and security. Increasing the block size to include more transactions leads to larger blocks, which are slower to propagate across the network.

This can increase the orphan rate and favor large mining pools, reducing decentralization. Furthermore, a faster block time to increase throughput can compromise security by increasing the risk of temporary forks and reorgs, which is antithetical to the security guaranteed by the Merkle Root.