One thing that critics of Thaksin seem to forget that he was elected. He, and subsequently his sister, were elected by the people. It was the Will of the people, a phrase that the UK remembers only too well of recent history.
He may have had his failings (We got Johnson, for heaven's sake) but the electorate chose his party for the change that they offered. A start an reducing the inequalities in this country, perhaps. Whatever, it was enough to spur the elites into action,