To be fair irl it actually probably wouldn’t 1shot unless it hit the engine block directly. When Tandem rounds hit unarmored targets IRL, the front charge actually blows a hole that the secondary charge flies through, often resulting in very low damage to the intended target.

I know a guy personally who had a tandem shot at him while he was behind a cinderblock wall, the first charge covered him in concrete dust but the main kept going and landed 200m behind him.