Is it reliable to watch videos and practice martial arts online?

Reliability and unreliability are mixed together. I think watching videos to learn martial arts is better than looking for a master to practice. Let's talk about the disadvantages of watching videos to learn martial arts: First, the movements are not standardized. Second, it is easy to get hurt. Third, it is not practical in actual combat. Fourth, save money. Fifth, energy is needed. Sixth, it can't play a role in strengthening the body.