Export Maya Reference with animation is extreemly slow compared to 'Cache to USD' workflow

**Describe the bug**
The 'Cache to USD' workflow (described here: [Caching animation to USD in Maya](https://youtu.be/XW9Pu2ep-kM) ) exports the [Mery rig](https://www.meryproject.com/) at about 5 seconds per frame. In comparison, selecting a Maya Reference at the root and then File - Export Selected to USD is 1 minute per frame(!) which is crazy slow. A 300 frame sequence here is 5 hours vs 25 minutes.

**Steps to reproduce**
Steps to reproduce the behavior:
1. Export using 'Cache to USD' workflow
2. select a Maya Reference at the root and then File - Export Selected to USD with animation
3. compare time per frame

**Expected behavior**
I would expect the time to be the same.

I note that both methods are slower than Alembic, which is less than a second per frame. Would of course be ideal to have the export speed of Alembic, but that is another issue.

Experimenting with ways to improve the speed I found that if I select the geometry group lower down on the hierarchy (which is all I want to export into a geo cache anyway), rather than the root and export that, the time goes from 1 minute to 5 seconds per frame. Perhaps this provides a clue as to the time difference between the two methods?

The above provides an acceptable workaround. If there are other things that can be done to improve the speed at a user level, I would be most appreciative to learn!

**Specs:**
Windows 10
Maya 2024.1 (USD 23)