Almost nobody doing industrial work with comparable PPE doesn't spend at least 1-2 hours of a typical workday out of the PPE.
The linked PDF has an example of a typical workday when removing asbestos, note how many times it involves putting on or taking off the PPE.
I'm not making any claim about COVID mask mandates, other than your examples seeming irrelevant to "chronic, day-in-day-out long term use of N95s".
https://ec.europa.eu/social/BlobServlet?docId=7478&langId=en