First, you can use the agent to go around the rules and possibly run into issues at a later time. Up to you if it's worth the risk. Second, are you sure you want to stay in TH over 180 days and possibly run into having to pay income tax? Might be better of just doing two 3 Month trips to TH and not worry about the BS...
while I realize it would be very difficult to completely eliminate them, there is lots we can do to reduce the use of them. Rabit Card, Usdt, USDC, Monero...
lol VN won't chase you for taxes, not sure why you would want to pay them in TH??? Setup an offshore company, run your business through it, pay yourself small salary and try to be a tax resident of country with most beneficial tax rules...
VN gives you a 3 month visa, so far no issue with staying here long time. Return flight between bkk and Saigon is cheap, the back and forth can be a bit much for some to handle, but there is no fing way I am gonna be completing more tax payper work just for the privelage of staying and spending my money in TH. Now as much as I do like TH, VN also has tons good things about it. 2-3 trips to TH a year should not be a problem at all. Apartment rentals also have way better options in Saigon than in Bangkok. Food can be healthier, and way better looking girls 😇