It doesn’t make zero sense that miners can be used for money laundering?

Unless I have misunderstood this (which happens..) a large mining operation can launder funds by creating a self-transfer transaction with an unusually high fee and broadcasting it only to their own mining node. In this setup, the transaction sends funds from one address the miner controls to another, while most of the value is assigned as a miner fee. Because the transaction is never propagated to the network, only the miner’s own node sees it, ensuring that no other miner can include it in a block and claim the fee.

Once the miner successfully mines a block, they include this high-fee transaction alongside regular mempool transactions. The excessive fee is then paid back to the miner as part of the block reward, effectively converting tainted funds into what appears on-chain as legitimate mining income.