Hi Robert,
1. No I do not have any joins with any feature classes within this geodatabase.
2. This is not an enterprise geodatabase.
3. Bingo, this was the issue. The ObjectID type is 64 bit (see screenshot) which I believe is because I imported the shapefiles into a new geodatabase created with the latest version of ArcGIS Pro. I was able to replicate this by using the workaround described at the tech support page and quoted below:
In the Options dialog on the Maps and Scenes page, check the box to Use field types that are compatible with ArcGIS Pro 3.1 and earlier releases when adding query layers and text files.
After flipping this option, I selected the original shapefiles, created a new geodatabase, and imported the shapefiles as feature classes into this new geodatabase. In the data source tab, I noticed that the ObjectID Data was now 32bit after I had used the aforementioned workaround. Now, I am able to export feature classes to shapefiles with no problem.
So, if I am understanding correctly, does that mean all new geodatabases are unable to export to shapefiles since they write the ObjectID as 64bit? That seems like a massive change that should be better advertised. I would at least like the option to export as 32bit or have some way to change the 64bit ObjectIDs to 32bit. Now I have a geodatabase full of 64bit ObjectID feature classes that I cannot export to shapefile which is common practice when distributing geodata in my office.
I followed the workaround below:
https://support.esri.com/en-us/bug/in-arcgis-pro-32-the-error-message-error-002809-field-o-bug-00016...