Those two nonfree programs have something else in common: they are both malware. That is, both have functionalities designed to mistreat the user.
If you use a program to carry out activities in your life, your freedom depends on your having control over the program.
Nonfree software was the first way for companies to take control of people's computing. Nowadays, there is another way, called Service as a Software Substitute, or SaaSS. That means letting someone else's server do your own computing tasks.
In some cases, nonfree software causes indirect harm (secondary injustice): it puts pressure directly on others to use this software (Teams, Skype, Zoom, ...), it encourages to develop the non-free software further. All the forms of indirect harm are magnified when the user is a public entity or a school.
Public agencies exist for the people, not for themselves. When they do computing, they do it for the people. They have a duty to maintain full control over that computing so that they can assure it is done properly for the people.