There are too many people avoiding the rules that are already in place.
Another one to add to the couple already mentioned is the 'wfh unless absolutely necessary'.
I have been WFH since March. There are about 10 back in from our department since July. (Large company, lots of different departments, I'd say at least 150 back in the office across all departments).
Now the 10 from our department, I can 100% say it's not necessary for them to be in the office, but they have been told to continue going to the office.
10 people might not seem like a lot of people, but that's 10 people in one department in one company. How many other people across the country are still going to the office when not absolutely necessary? - potentially crossing others on their travel to work, using the same doors, kitchen and bathroom facilities as others.
My brothers company are the same and the company he works for are nationwide - so many extra people going out to work every day when they could easily WFH.