In our specific case, we’re getting an error message like this when running on MacOS CI build nodes that have Cataline (10.16) installed:

10:00:50  Needed macosx_10_16_x86_64-cp-39-cp39 compatible dependencies for:
10:00:50   1: wrapt<2,>=1.10
10:00:50      Required by:
10:00:50        Deprecated 1.2.11
10:00:50      But this pex had no 'wrapt' distributions.

If I package the pex on a Catalina machine, then everything works. If I package it on Big Sur, it fails to execute the pex with the error above.