This is false in several ways. For one thing, Depp was an executive producer on this movie, listed second after Gore Verbinski. For another, Depp created this version of Tonto long before others were involved:
Depp's Tonto equal partner, not sidekick, of 'The Lone Ranger'
Depp is, of course, a master of disguise and a brilliant character actor as well as one of Hollywood’s best-loved leading men. He based his ‘look’ for Tonto on a painting he’d seen of a Native American warrior and added his own, unique, flourishes.
The result was spectacular and it convinced Bruckheimer—and indeed Disney Studios—that it was time for “The Lone Ranger” and Tonto to ride back onto the screen.
As Bruckheimer relates, “Johnny Depp creates amazing characters, no matter what movie he’s in. His Tonto will be different than any Tonto you’ve ever seen before. He has a whole different look, a whole different feel. We don’t even know until the cameras roll what he’s going to do, but we know it’s going to be entertaining and very interesting.”
Also note what this says about the so-called Comanche advisers. They're told Disney greenlit this movie primarily because of Depp's fabricated Tonto look. Their choice is 1) approve the look and receive fame and glory as Friends of Johnny, or 2) disapprove the look and be labeled the villains who destroyed a $250 million movie.
Wow, tough choice...not. The vast majority of the population would choose 1) regardless of the facts of the situation. So we can pretty much ignore everything the advisers said years after Depp invented his phony Tonto.
For more on Johnny Depp, see Lone Ranger Pitch Meeting, Critics Agree: Lone Ranger Is Bad and New Tonto as Racist as Old Tonto.