@Todd ********
You are correct. People need to file. Earned income from salary, investments, rental income, etc, may need to be paid in Thailand following taxes paid in the home country. That being said, many types of income are protected by treaty. The USA prohibits by treaty, sections 20 and 21 specifically, Thailand from ever taxing Social Security, military retirement, veterans benefits, state and federal pensions. Most Americans living in Thailand receive the lion-share, if not all of their monthly income, from the nonassessable income from the sources enumerated above. Very few Americans will be impacted. Those with IRA's, 401K's and actual earned income, I agree, will be. That being said, you are a Canadian national. Why are trying to be an expert on the USA/Thailand Dual Taxation Agreement Treaty?
Americans need 0 advice from unknowledgeable Canadians.
Have a nice day.