you forgot how long CO2 hangs around.
That's true, but it's irrelevant.
CO2 might stay in the atmosphere a long time, it builds up. And in the 160 years since the industrial revolution started, it's still only a fraction of water vapors levels.
I would suspect the amount of water vapor in the atmosphere is near constant. It's a true cycle. But it's always there.
How is the fact that co2 stays longer even remotely relevant?
Does co2's longer air time reduce water vapors power?
The oceans eat co2. Plants turn it o2 and other goodies that we build houses with.
With the super crazy amounts of water vapor, and it's superior efficiency at trapping heat compared to co2, it's almost like pissing in the wind.