Michael Fremer started doing this decades ago. Immediately people found they really could get a good relative sense of the way different high end cartridges sound. This was if I am not mistaken back before YouTube even was "a thing". Since then all kinds of people have used YT for this. I myself listened to Koetsu and Herron on YT before buying, and later Moab. To give but a few examples from personal experience.
The question never has been anything to do with the format, or the resolution, or how it was recorded, or any of the unlimited number of other irrelevant comments people will make. It always has been about the ability of the listener to discern and evaluate. Always has been. Always will be.
Everyone knows this. Right?
Oh, and it is possible to upload pics. Just have to do it on your system page.