Let us be a bit blunt here.
The violin is no where near as popular as the piano, guitar, or the drums.
It's actually a much more difficult instrument to play.
Because of this, you can't find a coach or instructor easily. If if you did, do they live in your city or town? Probably not.
You really want to get some instruction from a Master. If we were back say 20 years ago, how would you get lessons from a master violinist?
You're right, you wouldn't.
But now, with the advancement in technology, you can actually have a true violin genius teach you from the comfort of your own home.
That's the true benefit of online lessons. They allow you to learn from anywhere in the world.