I think the first part of what Trevino says is right. In that it doesn't matter what you've been taught, but out on the course what you do, for better or worse, is what you've learned. That doesn't mean that a good teacher can't help with the learning process.
To be fair to Lee, he says learning yourself has advantages - he doesn't say it's better. The whole self-taught thing is a bit moot anyway. What if you've never had a formal lesson but you grew up around good players and saw good swings, good rhythm, and good thinking on almost every round you played?
If you could take 2 players - and give 1 regular lessons but make him play all his golf on his own, whilst the other never gets a formal lesson but gets to play and practice with good golfers, I'd take the second guy to improve the most.
But anyway, I don't think Trevino would argue that Jack, or Arnie, or Watson weren't better players just because they got taught.