"Jimmy and I agreed there is no economic incentive to use bigger up returns, right? so it's basically two sides of a coin. If nobody's going to use it, we should not enable it or we are not worried about enabling it, right? But either way, if nobody's going to use it, it's probably a pretty marginal issue." - @Murch

I would say that there's no *obvious* economic incentives to use OP_RETURN, not that there were none.

And this is an important difference. To say that there are none is to say that you know all possible future things that people might use it for. I don't think anyone can know that.