Bullshit. The military deposed him because they were grabbing power and because they were worried about his close relationship with the crown prince.

Thaksin's power base lies in the rural poverty-stricken north. He was the first politician to actually help them. That's why he was so popular.

They all knew he was corrupt, but their choice was between corrupt who would help them and corrupt who would fuck them.

Thailand turned from a democracy into a dictatorship because of power hungry assholes. It had nothing to do with corruption.