Can a Miner Choose to Exclude High-Fee Transactions from Their Block?

Yes, a miner can technically choose to exclude any transaction, even one with a high fee, from the block they are mining. While this is economically irrational for the miner, who is incentivized to maximize profit, they have the freedom to do so under the current consensus rules.

This ability to exclude transactions is the basis of transaction censorship. However, if the miner consistently excludes high-fee transactions, other honest miners will include them, and the censoring miner will lose out on revenue.