>In 2013, an easy way to add data to any Bitcoin transaction was introduced. By making standard a previously invalid script instruction, OP_RETURN, a Bitcoin us

>In 2013, an easy way to add data to any Bitcoin transaction was introduced. By making standard a previously invalid script instruction, OP_RETURN, a Bitcoin user could add up to 40 bytes of data to his transactions. It was already plenty easy to convert data to a multisig transaction. OP_RETURN doesn't add to the UTXO, while multisig transactions do, so OP_RETURN is less harmful. This wasn't introduced to make it saving data to the blockchain easier, it was introduced to decrease the harm caused by spammers. It is more like a needle exchange.