In my view, if someone decides to take a test for themselves, they are clearly making a statement to a certain degree, albeit to themselves, that they care about whether they have Covid or not. There is obviously some concern otherwise they wouldn't bother to take the test, unless it is a requirement for work perhaps.
If they, themselves, feel some concern about whether or not they have Covid, then they would surely understand that others, too, might share that concern. Illnesses tend to affect different people in different ways. What may appear as a light cold to some might appear much more severe in others or affect others in different ways. For example, I suffer from chronic labyrinthitis and catching a cold causes me to suffer from quite nasty vertigo, in addition to the other cold symptoms, because colds affect my ears.
So really, it doesn't matter what the government recommends. At the end of the day, it is up to each individual to understand that not everyone will wish to share their infectious illness for their own personal reasons and keep away from others until they are no longer infectious.