Had Qui-gon Jinn lived to train Anakin, he would have had a chance.
We never hear Qui-gon say or show that he’s against the no-attachment rule. That’s just fan conjecture. I’m still not convinced that Lucas viewed the Jedi’s rules on attachment as an unhealthy thing.
We know that Qui-gon often went against the council. So he was a bit of a rebel. He may have been able to teach Anakin to handle his attachment issues. I agree that Lucas included a subtle feeling that the Jedi rules on attachment were wrong, but there is nothing specific. But he did tell Dave Filoni that had Qui-gon lived, Anakin wouldn’t have turned to the dark side. The light saber battle in TPM is about Anakin’s fate. Qui-gon died and with him the chance for Anakin to stay on the light side.