This is true, but I think the card would be better reworded to reflect this. The current form is not ideal anyways, as it has a dividing line that shouldn't be there. I would suggest
Move your Sanction token to a supply pile. At the start of your next turn, take it back and +$3.
Until then, when any player plays a card from that pile, they first take 2D.
The Copper sanctioning is still a problem and can lock people out of the game if you have a $5/$2 opening.
Whelp I really was tired when I made this. Missed both the horizontal line (?!) and the fact that it can hit Coppers. I very much want it to hit custom Treasure cards but not Copper/Silver/Gold. So "Kingdom supply pile" should do it. And it shouldn't have the attack type; it's an attack like Embargo that doesn't have the type bc the interaction with moat is awkward
Updated Version (it's fine if this doesn't make it into the contest anymore).

I think it could be an Attack just like the other duration attacks Blockade and Swamp Hag are. The only difference to those two cards is that TB can also hurt the player themself, but this is rarely relevant when sanctioning an Action, and Moat clearly states that it only reacts to another player playing an Attack, not to your own Attack. TB hurts the opponents badly e.g. when sanctioning the only village or a strong cantrip.
Unrelatedly, you don't need a token if TB sets aside a copy from the pile instead (like Blockade, but returning it to the pile next turn).