The 500.000 Baht deposit is meant as guarentee that all DTV users always will be able to pay everything for them selves, even accidents and other sudden events, so they will not be a burden for the Thai citizens.
That’s also the reason why it will be unwise to dig to deep into the deposit, you may end up not being treated at hospital, until you have payed.
Or similar occurrences where a big amount of cash is needed.
That’s why most Embassies demands 2 times 500.000 baht deposits for 2 persons, each a seperat account in their own name.
Banks in Thailand are like everywhere in the world, interested in having good stable customers, that have a permanent address, a steady easy traceable income, and use the account all year round.
That is why the banks are reluctant to give accounts to people on short time ( read: tourist ) visas, and who only spend part of the year in Thailand.
Don’t expect to get a residence certificat, until you have stayed at a permanent adress in at least 3 month, since that is what the residence certificat should confirm.
Furthermore the added attention on whitewashing of money, is an added burden on the banks, so reluctant depositing large amounts isn’t a guaranteed way to open an account.
The value of a resident certificat, had gone down, since Immigration Officers are giving them to people that are not on a longterm visa, or have stayed severel months at 1 adress in Thailand, so even if it is a formal requirement, the bank make up their own assesment of the stability of the want-to-be customer.
Be aware there is a error in the start of the article ( and several other copy - paste media with the same article )
A Thai Bankaccount has never been a requirement to get DTV, on the contrary it has been one of the big advantage over other visa, that you could get DTV as long as you could show 500.000 Baht equivalent in any bank anywhere in the world.
It has never been the intention that DTV visaholders should be in need of a Thai bankaccount.
If choosing ED, you have to be actually studying full time, show up to all classes, and pass tests.
It is also depending on what to study, several people has gotten an ED visa instead of the DTV, if the ED is better suited to the reasons for applying i.e. studying Thai language.