No, but if you spend 180 days or more inside Thailand in any calendar year then you are automatically a Thai tax resident. If during that calendar year you bring 120k baht of assessable income or more into Thailand then you need both a TIN and to complete a Thai tax return
He would first of all have to travel back to his home country to apply. Then the embassy in that country might or might not issue him with another METV. Then immigration might or might not deny him entry. I've seen reports of people trying to squeeze an additional 60 days out of an METV just before it expires being denied entry, so I would suggest his chances are not good. Probably best to leave Thailand until he has saved enough to apply for his desired visa. It's really not possible to live in Thailand any more on tourist/visa exempt entries
it does give you multiple entries meaning you can leave and return as often as you like during the period of your extension of stay. But a Non-O multiple entry visa only allowed you to stay for a maximum of 90 days at a time then you had to leave and return (but that visa is no longer available)