>>535159884
That's because Lab is not a stun archetype and is only sometimes a stun deck. Lab is a very versatile archetype that's been built in a ton of ways.
You can choose to run floodgates and turn it into a stun deck as many do. But also many run the deck without floodgates or without a heavy emphasis on them. You'll also see people run floodgates in White Forest or Snake Eyes, but just calling those stun decks and leaving it at that means you don't know what you're talking about or don't care to give an accurate assessment.