Some, but not others?
Discussion
No they are all on, it's just a matter of the thresholds. By default the OP RETURN data can hold 80bytes of data. You can raise or lower this limit. The PR is to remove it entirely. If they do, you can still run a node with whatever limit you want and you would still be in concensous.
Thanks. Does pruning remove this data by default?
No. Pruning just removes txins up to a certain checkpoint that you define. It doesn't care what's in them. But also this is for mempool policy. ie transactions that have not yet been confirmed. Once a txt is confirmed, every node will store it. No matter what their mempool policy is