Parroting the rest here, but for different reasons:
Even if you're a real life martial artist, you need to study form 1. You're learning a new martial art regardless of your own skill. You're learning a new weapon that is all edge, and no flat. Knowing a weapon style gives you an advantage, but not much.
Always begin at the beginning. You can have a black belt in one school, you're still a beginner in another.
You are right ... "from a certain point of view."

I have always considered Light Saber fighting as the equivalent of MMA. I mean, for me, Light Saber is a weapon used by species from an entire galaxy with different cultural backgrounds and different anatomies. For me, the different "forms" are only because of that ... Lets consider a Human being from a peaceful planet and a 7' tall Alien from a warrior planet. They should have a very different style ...
What i love when practicing Light Saber, it is that people from different cultural/martial backgrounds use the same weapon. And it is very fun for me. With my own background, i learn a lot when i fight with a fencer or a kendoka.
But if you consider LightSaber as a Martial Art and not the equivalent of the MMA, you are absolutely right