I was being a little bit facetious but yea I think the bar for playing a 4 mana card in a control deck is pretty high especially when it's just a value piece, then you have to ask is it better than ring? Usually these slots are limited to stuff like emperor/comet/Karn that can actually function as wincons (I guess you can revive Kaya with court or something to kill the opponent but thats an extra hoop to jump through)

To some extent I agree that you don't always want the top end play of your control deck to be dinky 2-for-1s like Snapcaster KCommand but this deck already has Estrid 4x and idk if it needs to go any harder into the Phyrexian Arena plan