What Is the Main Difference between Block Rewards and Transaction Fees for Miners?

Block rewards are newly minted coins granted to the miner who successfully adds the next block to the blockchain. Transaction fees are payments included by users to incentivize miners to include their transactions in a block.

Post-halving, the block reward is periodically reduced, causing transaction fees to become a more significant component of a miner's total revenue. Both are crucial for incentivizing the security of the network.