Tony Northrup: high megapixels is best for low light & high iso

Tony writes:

Low megapixel cameras have less noise in low light because of bigger pixels, right? Camera manufacturers AND smartphone manufacturers use that in their advertising, but is it true?
NO. We put three sets of cameras to the test, for both still images and video. The cameras tested include the Sony a7S III, Sony a7R IV, Sony a1, Canon R5, Canon R6, Fujifilm X-H2, and Fujifilm X-T4. In EVERY case, the high megapixel camera outperformed the lower megapixel camera in low-light, high ISO photography AND video. Every time.