Even if you can have it transcribed (which is possible today), videos contain far more information than what is spoken: gestures, emphasis / how words are spoke

Even if you can have it transcribed (which is possible today), videos contain far more information than what is spoken: gestures, emphasis / how words are spoken, body language, objects, diagrams, etc. While skilled speakers may try to mitigate that so that the presentation degrades somewhat gracefully to a transcription, it's by no means a one-to-one translation, and it doesn't always make sense.