Ultrasound is extremely non-penetrating and wouldn't make it through the walls of a building. Infrasound is the opposite and would go through most anything, and in principle can be produced by anything that moves, but the thing to care about at those frequencies is the amplitude, i.e. the sound volume. It's a meaningful concern from things like wind farms that have massive slow-turning turbines, but there is nothing in a data center that moves that kind of volume. On top of that, having multiple independent small sources in the same place lessens the effect, because multiple sources that emit at the same frequency but out of phase with each other cancel each other out.

Undoubtedly if you get some measurement equipment and stand next to a data center you could register some infrasound, but the same would be true if you stand next to an ordinary office building or in an empty field, because infrasound carries for hundreds of miles and there are much larger sources than data centers.

"There is a sound but you can't hear it trust me bro" is solidly into YouTube quacks territory.