Sharpness, alongside exposure and colour balance, are fundamentals of photography and not at all amateur-only concerns. Normally, people will want areas of interest in a photo to be clearly “in focus” – often, as sharp as possible, as accurate as possible a representation of what’s in front of camera. Of course it’s not always the case that max sharpness is desired – but it’s much easier to soften a sharp image than to construct detail not recorded.
Sharpness will dictate how much detail an image can reproduce (a lens can resolve, a sensor capture.) So resolution tests can involve series of increasingly tightly-packed lines, and then a comparison of how many lines per unit length can be distinguished in the captured image. https://www.imatest.com/docs/sharpness/
https://www.digitalcameraworld.com/2012/06/26/test-your-lens-sharpness/
Digital cameras (as well as early analogue video cameras) often allow an artificial sharpening process, or edge enhancement, to give an image a cleaner, clearer look. https://www.cambridgeincolour.com/tutorials/image-sharpening.htm This sharpening can be added in post for stills or video, and sometimes people like it, or some people like it.
On your specific test (which I haven’t seen), it’s not unusual for tests published online to be not that strictly set up or controlled in a “scientific” neutral, accurate, reproducible and balanced way, to measure a clearly identified property … And often people will feel hostile to published results that do not confirm (or run contrary to ) their expectations. This effect can be enhanced when people are identified with a specific brand or item of kit which they take to be and want to be “the best” – particularly if it’s kit they’ve spent $$$ on. Some brands encourage that kind of product identification, choice and loyalty in their promotion and marketing (a good way to add profits, if people will pay a premium for the brand independent of actual performance, features and functions) and it may be that some of the camera makers whose kit was tested in that survey use that approach to customer communications.