I'd agree as far as trying to learn from video
alone. On the other hand, as KPM, Buka, and others have said, video can be a great supplement to live, in-person instruction. And, for advanced practitioners, ideas gleaned from videos can really be helpful. At least that's my experience.
The real problem for me is that watching videos (as well as reading books, and discussing technique verbally) and trying to apply the material with some reasonable semblance of functionality is
way more work, and
way more boring, than training in class under your instructor. And then you
still need to run it by your instructor to get it right.
One thing I've noted as a student whose instructor lives 1,000 miles away, is that if you
have to figure things out yourself, even though you may need to get the details polished later, you will really understand the material more deeply than students who simply mimic an instructor without knowing why they are doing what they do. ...Of course having some decades of experience in the art is helpful too.