The shitcoin BSV has had OP_RETURN of 100KB since 2019 💩💩💩
💩This is all made possible of course by the nChain team raising the limit on the OP_RETURN feature. By increasing the size allowed for OP_RETURNs to 100KB, BSV has opened up a new world of possibilities, and taken on a new form as not only the money of the future, but the data carrier of the future.💩
https://coingeek.com/bitcoin-sv-op_return-stats-unlocked-by-whatsonchain/