Yes, absolutely. The fact that PC sales are normally very low (around a tenth) of console sales for the same title and games without multiplayer are pirated at a much higher rate than multiplayer games is common knowledge and entirely uncontroversial within the game development industry, and always factors into decisions about how much money to invest in PC titles. Pretty much all the major shifts in PC gaming since the late '90s - cheap console ports, the emphasis on multiplayer, MMOs, Steam, etc - have been responses to piracy.
So you're saying that since the difference in PC game sales versus consoles can be accounted for primarily by piracy (not difference in demand), and that PC game sales are 10% of console sales--that 9 times as many people pirate PC games as buy them?
That doesn't take into account that many of the pirates wouldn't have purchased the game if piracy wasn't an option. If we consider that, then we'd need many more pirates, maybe twice as many (18 times as many pirates than purchasers in total), to account for the lower PC sales.
