EmRR said it well. When you say "artist" you usually mean a vocal soloist, I think; a lot depends on their level of experience and technical awareness, which varies. Producers and engineers tend to defer to the performer when the performer has definite opinions, unless the performer has an unusually cooperative personality (some do, but some REALLY don't).
Complicating the situation is that someone may arrange for "session photos" to be taken, showing a certain type or brand of microphone in use, when in fact the performer didn't/doesn't use that brand or type of microphone, at least not exclusively. Perhaps those microphones are being "lent" to the producer or performer, and coincidentally, no one will ask for them to be returned later. Photos of this kind go back to the 1960s at least, including cover photos for record albums, and they really make it hard to find out the actual situation. Sometimes you notice that the microphone is backwards or sideways from the way it's supposed to be used, or that the cable isn't plugged in but the singer is making a very expressive face as if they're in a state of rapture, like as if someone was doing something very nice to the part of them that was beneath the frame of the photo.
I would also say that ~80% of all quotes that supposedly come from performers about the greatness of a certain microphone (or other recording equipment) are phony quotes, approved by someone's agent as part of a business deal. For a person who isn't actually in the studio, it's practically impossible to find out what equipment was actually used. When I worked at RCA Studios there was a non-disclosure agreement in general effect, and only the higher-ups were supposed to make any pronouncements about methods and equipment used in recordings; the truth value of such pronouncements varied with whoever pronounced them. Even the little technical notes on the back of the LP or CD were often less than factual in my experience; record companies aren't necessarily very careful with credits, and what got listed often depended on politics rather than a penchant for accuracy and honesty.