Consequences of Tidal Dissipation in a Putative Venusian Ocean

> Consequently, an ocean tide on ancient Venus could have had significant effects on the rotational history of the planet

The implication seems to be that we could answer whether Venus once had water, based on the orbital history of the Earth (over very long time frames), I guess?

That never occurred to me before this moment, but of course the dense atmosphere would tend to exert some tidal drag. The above sentence indicates the atmosphere alone suffices to explain the slow rotation.

But that would seem to flat-out contradict everything else said here. The atmosphere, not the ancient ocean, is the explanation. What am I missing?

Such a moon must be very rare, for rocky planets in the Goldilocks zone. There is a plausible argument that life would not have developed at anything like its pace, without.

That might resolve the Fermi paradox, unless warm gas-giant moons are common and not all bathed continuously in ionizing radiation.