I’ve also done it with the microplane but you do lose a lot aesthetically. Yes, theoretically increasing the surface area is supposed to give you more aroma.
Practically though, with good truffles and ample shavings the aroma and taste isn’t that much stronger with a microplane vs thinly sliced via truffle shaver.
And there is something to be said about the beauty of the white truffle sliced vs grated.