I think your questions were already addressed in OP. See this section. The legality of stored data does not depend of its encoding. Even if it did, it is trivial to get a large OP_RETURN output mined today regardless of the Bitcoin Core policy change. Assuming an attacker cannot pay a couple dollars premium or is unable to simply use a website is an uninteresting threat model. This risk is fundamental to Bitcoin, the proposed Bitcoin Core policy change does not materially affect this concern. What does make a difference and could put node runners at risk is fear mongerers trying to draw more public attention to this already existing issue.
1 Like