I once took a retired Police Officer who had a couple under his command transfer to Immigration as a whitntess to my marriage Just in case I needed a marriage visa however turns out he was not needed as they accepted my paper work for extension based on retirement. However my Visa was processed with the speed of light.
while what you say is factual the US Government does impose reporting on its citizens it has zero do do with a branch opening or not opening an account here in Thailand. The Europeans have the same difficulties. With my Yellow Book I have zero problem opening accounts as it about documentation.
It has effected jobs for my Thai Relatives and rental cash flow for my wife but the impact domtar is minor compared to many Thais in the Hotel Industry.
Have done my own Retirement Extension Paperwork for 20 plus, No mountain of paperwork, easier before yes, and no stress just follow the rules as they change,. This year 30 minutes with 12 deposits over 65K and out I went with a smile.