You're being generous. His record in Sri Lanka is only marginally better than his record in Australia. His record in the West Indies is good... but that's because playing in the West Indies generally means you are playing against the Windies -- one of the poorer teams going around.He's also got a better strike rate in India, Sri Lanka and the West Indies than he does in Australia, too, so he can take wickets in spinning conditions as well, despite some poeple's apparently certainty that he can't/won't.
His record in India? Yes, his strike rate in India is better than his strike rate in Australia. But his average is worse. That's because he gets spanked by the Indians at more than 4 runs an over... and that is why people don't think he'll do well.
Back in 2015, it really looked like Lyon had turned a corner. He wasn't taking big bags, but he was regularly taking 2-3 wickets each innings and was generally tight. But this year he's got steadily worse and in the last couple of weeks he has been complete poo. The fact that he took 3 quick wickets in Melbourne and wasn't given the ball to try and clean up the tail just shows that Smith has very little faith in him.
There's a breakdown somewhere and it really needs to be fixed.