Prior to 2019 the Article 32 was considered a discovery mechanism for the defense to make timely informed decisions and was to be a "bulwark against baseless charges."
Now, the hearing is intended to do no more than allow the prosecution to present enough evidence to establish probable cause--just like civilian cases.
Of course the commander still is allowed to refer charges to trial even if there is no probable cause.
The joke among lawyers is that any prosecutor can indict a ham sandwich; now the military joke seems to be that you don't need the ham.
Yes you can get some discovery at a "new" Article 32 preliminary hearing. In January 2015 Article 32 was changed to make it easier to refer charges to trial and prevent the defense interviewing under oath a complaining witness the a military sexual assault. The changes were intended to shield witnesses from being challenged and make it hard to defend against false allegations.
No longer a bulwark against baseless charges, courtesy of Congress, you can still get discovery at the "new" Article 32, it's just not as much. As a civilian military defense counsel I am constantly exploring ways to get early discovery in a case so we can make the best decisions. Pretrial discovery is one of the core competencies your military defense lawyer should have.