That could be entirely possible, because they have gotten more stringent recently. But it would also be fair to mention that they also didn't have the E10+ rating back then, which probably would've been appropriate for OOT, because it's not exactly E, but it's not quite T.
It says on the TP box that it contains "Animated Blood", but I don't recall seeing any, or much at all. And besides, my version (GC) of OOT had green blood.