Again, retirees probably won't be using a DTV visa. The DTV visa is intended for people on "worcation"; people that have an occupation in another country that can be performed remotely.
The 180 day limit was by the OP said to be a good thing for those who like to travel. I clarified a real life legal reason why it's a good thing. If you think that is unnecessary, then you are probably not the type of person who cares much about rules and regulations. That in turn makes everything you bring to the table less interesting. Good for people partaking in the discussion to know.
If you have a lease in your name, a employment contract in your home country that says you work remote and a registered sim-card, you could probably open a bank account (with the help of an agency)