That’s incorrect. You can burn bitcoin if you want to with OP_RETURN but you can also use it without burning it (sending 0 to the unspendable address). The fee you pay to miners doesn’t leave circulation.
OP_RETURN was added to discourage other data storage schemes on the blockchain. People were already recognizing and utilizing the immutability of the chain to store non-financial data, and they’re still doing that to this day with ordinals.
OP_RETURN didn’t introduce the idea of storing other data on the blockchain, it made it orders of magnitude more efficient (storing hash proofs instead of the data itself, and allowing nodes to prune the output as unspendable)