if they're on the crust, that could be interesting texture-wise, but as a condiment itself, it'll be lost in the sauce, giving it just a slightly gritty texture and lack of visual appeal.
They'd need to be toasted, but as far as I know, the aroma would be overpowered by the sauce in most cases. But if it's a mostly cheese one or other that doesn't have that strong a strong scent normally would be able to improve it.
So while I think it could work, in most cases the scent would be masked to much by the rest of the pizza.
yeah, the most effective application would be on the crust, maybe with a garlic oil wash? that could provide additional flavor to accompany the unusual texture