Props for reminding me of the first deck I ever won a MtG tournament with (I’m assuming that’s what you meant by Fish - Merfolk with Winter Orbs)! Good memories 
I agree that blue has control elements (mostly in Law and Truth), but is not an old skool MtG style permission deck. For what it’s worth, I don’t think there is a codex permission deck, almost all codex decks which I have seen use units as an essential element of both their offensive and defensive line-up, whereas the MtG Blue decks I think you’re referring to didn’t really.
I don’t think it’s misleading to say that Blue is the control colour, as you’ve already pointed out, aggro-control is in some sense a control deck (the clue is in the name). Purple has elements of control (esp. Past), but I would say is largely characterised by extremely efficient tech 2 units (and so in my experience often plays more like a MtG mid-range deck).
I haven’t played Magic in more than 15 years though, so I could be misusing deck descriptors as the game has changed a lot.