Some people do both. Also, people can be keen observers without being practitioners.

Also, some things get labeled as science but arguably shouldn't, because of the massive distinction between rigorously evidence-tested knowledge and speculation couched in the right kind of language and given a pass by one's pals.

It is true that the epistemology of science is largely descriptive; people take the general idea and an apprenticeship to an established scientist and run with whatever they think works; philosophers are mostly left to sort out what actually did work and what the reasons were.

"N=1 is not good" isn't a rule that any thoughtful philosopher of science would endorse. Nor would any thoughtful scientist. The reason is that N=1 is an existence proof (philosophers of science generally know logic) and often there is a lot of detail to the "1".

It's much harder to evade falsifiability, however, once you go beyond data-gathering to trying to understand. I can't offhand think of even a single instance where you can do away with that (assuming that you count proofs and calculations), even if you don't state it in those terms for practical use.