IMO the term ‘card’ should never be used to refer to a creature or support in play.
In fact, IIRC, it wasn’t used like this in MTGPQ until 2021, with Midnight Hunt, when Oktagon got lazy and used it on Spell Queller and Teferi, Hero of Dominaria. It caused a lot of confusion at the time.
If you think about it, it doesn’t really make much sense from a linguistic point of view, because a Vanguard is a card (you had it as a card in your hand, you cast that card to put it into play, and it will be a card in your graveyard after it dies!) but it’s unaffected by Spell Queller (because an effect will not affect a Vanguard unless it explicitly says so), but a token is not a card (it was never in your hand and will not go to the graveyard), but it will be affected by Spell Queller.
Personally, I think the best thing to do is stop using the term “card” to refer to things in play in the future, and only use “card” to refer to a card in hand. For things in play. we could adopt the term “Permanent” from paper MTG, or just write “Creature or Support” which frankly isn’t much longer to write and is easier to understand.