Expert reactions to this, from Science Media Center, containing besides the main subject also some insights about why some members of a household in which the others tested positive, can't get a positive test.
Has to do with the immune system.
I had that during my second covid infection with probably Omicron, the first was most likely Delta.
I was clearly infected, family members positive, I repeatedly negative, although I did everything medically possible to get a positive test on purpose (need the newer certificate for travelling and other things), with the help of family, didn't help, although I had the same symptoms and new loss of smell and taste...
And some ideas about possible future variants in the text...
http://www.sci encemediacentre.org/expert-reaction-to-study-looking-at-cross-reactivity-of-t-cells-from-common-colds-and-protection-against-sars-cov-2-infection/