Journals are incentivized to publish fantastic results. Organizing raw data in a way that the uninitiated can understand it presents serious friction in getting results out the door.

The organizations who fund the research are (finally) beginning to require it [0][1], and some journals encourage it, but a massive cultural shift is required and there will be growing pains.

You could also try emailing the corresponding authors. Any good-faith scientist should be happy to share what they have, assuming it's well organized/legible.

[0] https://new.nsf.gov/public-access [1] https://sharing.nih.gov/