That means that the shortage is between 3% and 5% of the total homes available in the US (around 140M). And given there are under 700k homeless in the US (I wish it were lower, but it is lower than I was expecting before looking it up), most people are finding homes to live in.
By most measures, and given how new homes are being built every single day (and are very, very likely being sold as soon as they're up), it's not even remotely close to "woefully inadequate".
And for a moment, let's just say we agree and the supply is woefully inadequate. Two things can be true at the same time. A shortage of housing supply dovetails nicely with landlords colluding to identify the highest possible price point for their housing.