Listening on YouTube to determine actual sound quality of a piece of audio equipment is of course useless…… It’s similar to try to discern the overall quality of a high end car or camera or even a restaurant range ( I’m a chef / restaurateur).
You can get an idea of the looks & features & see if it’s something you might want to pursue but that’s it. There are simply too many potential points of degradation along the way. Unfortunately w/ fewer & fewer actual good quality stores to listen stuff in person, it makes it difficult. I think now the audio shows are a good alternative although the sound quality at them can be quite varied.