Edit: Solved. (Reversing mouse wheel zoom direction setting gets erased.)

Edit: Got it. I skipped over the commented section when looking at the env file. Force of habit.

"Put custom settings above this line." That took care of it.

I found this post from some years ago, which helped, but...
https://community.cadence.com/cadence_technology_forums/pcb-design/f/pcb-design/39912/pcb-editor-how-to-change-mapping-of-mouse-wheel

I added some lines to PCB Editor/Designer's env file:

button wheel_up "zoom out $buttonfactor"
button wheel_down "zoom in $buttonfactor"

They worked, that reversed the mouse wheel zoom direction.

Then I made a change in the User Preferences Editor. It didn't modify the env file, it overwrote it, wiping out the changes I'd made. Is there a section for user-entered settings, or a way of protecting them so they won't get wiped out as I customize OrCAD?