The correct answer is:

The proper buddhism properly penetrated in all levels of society, especially the wealthy and the ruling class, both public and the puppet masters. There isn't actually much puppet mastery in Thailand, it seems. Wysiwyg. That is good, and that is also a result of proper buddhism.

Proper buddhism is the one based on the Pali Canon, not any other texts, and especially not any teachers. Especially not any other religions nor lack of one.

Humans still make mistakes, of course. But with proper buddhism sufficiently well rooted in the society, there is looooots of buffer.