I don't know much about chess but Magnus throwing away his queen like that (traded his queen + rook for two rooks), was that a common thing to do? Looked outrageous to me but what do I know.
A queen for two rooks is not too crazy, whether it's worth it depends a lot on the position. The naive piece worth suggests that two rooks (5 each) is worth more than a single queen (9), but in practice it's more complicated. I would say though, as someone who's not amazing at chess that was definitely one of the most significant moments in the game for me - Not that Magnus was making a mistake, but that he was creating a very big imbalance in the pieces which was going to make the game get a lot more interesting.
There are values associated with pieces. Without considering the position, a pawn would = 1, Knight = 3, Bishop = 3.5, Rook = 5, and Queen = 9. I've not seen the game yet, but if he traded a Queen for 2 rooks that isn't such a bad deal.
Modern engines value the pieces more, like knight/bishop ar 4.1, rook closer to 6 and queen at 11.
It looks like he traded just his Queen for two rooks.