It makes absolutely no legal difference, it makes no functional difference.  You already noted anyone can do it by mining a block, which you can do at a fairly minor cost using nicehash or other similar services, but you don't even have to because as was demonstrated at the start of the discussion major miners (and likely a majority of hashpower even!) were already mining op_return above the limit!  So it's already there, even before all this discussion.  The world hasn't ended.

What bitcoin core does doesn't matter when it comes to policy, what miner do matter.  In particular, even a small minority of miners not enforcing a policy makes it complete moot. And this is good because the fact that information is easy to spread and hard to stifle is what is protecting bitcoin from outrageous financial censorship.  Bitcoin core not relaying transactions which are readily mined only hurts Bitcoin by promoting centralization both in the form of direct miner submission which increases income for the largest miners, and harming block propagation which improves income for the largest miners.

Though anyone convinced that it makes a difference is free to write a few-lines patch to change the serialization to make any of the encoding non-contiguous.   Of course, no one is doing that because the "concern" is just fake.

All where seeing here is just more desperate lying and goalpost shifting by dishonest attackers who are desperate to seize any meaingless fringe.    Up thread, the allegation was made that bitcoin core contributors were into shitcoins.  I challenged for any substantiation-- and I get just crickets.  Now the thread is going on about 'contiguous data' .