Personally, I don't doubt that at all! I work in a field that heavily relies on being able to contact people and have them provide products so I can get my work completed. Time and time again I have had to delay deadlines because people simply do not answer their phones, emails, or complete their work in a timely manner. When you are waiting 2 weeks for a simple email reply or 1 month for a minor work product to be completed, there is a problem.
I'm going to call bs on this being a WFH Issue