The disadvantage of a retirement visa vs a DTV is the DTV. If you’re eligible for a retirement visa don’t think about a DTV. It gives you nothing better than a retirement does, and you have to leave the country every year instead of just renewing the retirement.
You are a long-term resident vs you are a tourist allowed to stay longer. Non immigrant visas are better in every case, except the ease of getting the DTV.
they may invite you to visit the branch and ask for a visa update once it expires. If you’re unable to come or prove your long stay, they most likely will close your account. Bangkok bank doesn’t want tourist clients due to the internal problems they had. If you’re in a long-term visa such as retirement or marry, they won’t make you problems.