This isn't quite right; the University of Chicago study replicates what has already been known for a long time - that musicians can develop their pitch memory around the timbral context clues of a particular instrument. However, this learned pitch does not generalize to other instruments and/or common everyday sounds (train horns, washing machine vibrations) in the way that people with absolute pitch can instantly identify.

An analogy to this might be that a colorblind person if shown enough fabric and told what the colors were can eventually associate the texture of the fabric with a given color and can learn to do this translating in their head, but they will not be able to train their eyes to see color no matter how much practice takes place.

Rick Beato covers the subject rather well in his video "Why Adults Can't Develop Perfect Pitch" https://www.youtube.com/watch?v=816VLQNdPMM

If it were the case that such a substantial number of amateur test subjects could develop absolute pitch from doing a few exercises, we would expect to see commensurate numbers of musicians who spend thousands of hours playing music to also develop this skill, but this is not and has never been the case.