At CentML, we profiled GPU utilization on a larger AI/ML research institute cluster. 10% to 45% range, mostly in 10% utilization range. We then offered them software optimizers (which do not affect model accuracy) to get to the 90% utilization for GPUs
90% sustained utilization is quite amazing, and 10% is shockingly typical. I am a quite skeptical that this holds for training and very large data sets, of the sort where data placement comes into play, but if so, congratulations, and I hope things go well for you.