I think is this:
yes you can already do it and at a discount, but in a way that is a “work-around”, namely in a way that the network is not endorsing and is not intended to be used for. This distinction might not matter from a “technical” point of view, but it matters from a “legal” and mostly a “what is bitcoin for” point of view. Here we are trying to onboard family and friends to bitcoin presenting it as money, which is already hard as fuck, and on top we gotta say “yes the network also allows and now facilitate relay of data that is not monetary, but don’t worry about that it’s mostly money trust me”
The idea of “open to every data and money/data will eventually win” is great and I endorse it, but I think it’s too soon for that and mostly it’s not realistic for the present environment. Can you imagine a normal person (and we need to onboard these kind of people) saying “oh yes freedom all the way, who cares if someone relays illegal data, I’m in it for the monetary network”
Also, while people can already do it, making it easier for them (instead of having to go directly to a miner or making memepool policy harder to really this things) is again removing friction. And this friction matters (please don’t tell me you believe in the “but this contributed to miner centralization narrative).
And after all this, even if this op_return things is technically ok, aren’t you worried from the behaviour that some of the main core devs have been displaying? Because for many of us is not about “I love knots”, it’s about “holy shit there’s something wrong going on with core”