The main problem with videos seems to be what different people are trying to convey and what different people are trying to get out of it.
The listeners are on a gamut from I think this one video qualifies as an entire system audition, to those who try to get characteristics of system and component over time through compares. This is no different from how different people treat hifi shows. It's also no different to someone looking to buy a piece of gear who will do so at the slightest positive written comments while others will do a more deep dive
The system owners have a varying range of sensitivity which is reflected into the videos. For the posters please think if your video is representative of what you heard before posting. Some are, and some aren't. I am sure by now many who haven't posted must have heard their own videos played back
Yes, I don't find videos entirely useless, but it is important to manage expectations when listening to them.
The best use I think is direct comparisons of components, with all else being the same, including recording equipment and position. Then you can listen for differences in tonal balance, for example. Tonearm/cartridge videos can be quite instructive in that respect. Just don't expect to hear the absolute performance, only relative differences.
Videos can also be useful in shattering preconceptions.
For example several people found Peter's system videos useful and enjoyable as they, correctly, suggested that you can get a warm, natural sound from Magico speakers rather than the stereotypical 'clinical' sound. I knew that already, but the fact that I could hear that basic characteristic in Peter's choral videos was a main reason why I encouraged him to publish them (not that he needed my input). His videos of Carla White and Scheherazade I think deepened that notion of a natural, even full bodied sound being possible, even though the absolute sound quality is much better hearing it in person.
Or you can hear, which I personally find useful, that horn speakers can have a quite 'normal' timbre, without the infamous stereotypical horn colorations, at least not in an entirely obvious way which would come through in any decent video. You can also hear good basic resolution on violin sound, for example. I really enjoy those experiences. Do I draw absolute conclusions from such videos about the actual timbre from such systems? Of course not. I still hear flaws, but these could very well be the recording. The main point for me is hearing a more or less normal sound from a variety of horn speakers, which in itself is quite revealing.
On the other hand, I have never heard dynamics from those horn system videos that exceed the dynamics of my system heard in person, and often the dynamics are less. So in that sense I have not heard yet the reason for being of such horn systems. But do I draw absolute conclusions? Of course not. I might still be blown away by the dynamics of some horn systems hearing them in person, who knows? (Even though my own standards for dynamics and liveliness are *very* high.)
So it is important not to get carried away into absolute conclusions from videos, while on the other hand appreciating the usefulness of hearing some sound characteristics from such videos, which otherwise would remain unknown without any video evidence to those who have not heard the system in person.
Of course, hearing a system in person beats any video, but given the above, it seems to me videos do have some limited usefulness which can be quite enjoyable.