I've been in and out of the country several times in the past few months with no onward flights booked, and haven't been asked once. I do have a Vietnam trip booked early next year, but still never been asked about onwards flights
He's correct. I've been coming in and out of Thailand since December last year and the immigration staff are awesome. Check passport in system, check TDAC, welcome back to Thailand enjoy your stay
Funny that if you're polite and courteous to the IO staff, they will just do the job and you're on your way. Act like a pelican anywhere in Thailand and they will give it straight back to you. I've seen a person interact with a police officer at a traffic stop in the same manner for no reason at all, and he ended up in handcuffs 🤣
Take a print out of the DTV as well, just to make things easier for the immigration officer. I've had one that didn't want it, and several others that scanned the QR code on the page. It's not necessary but they seem to prefer it
In Australia, I sent a screen shot of my bank balance and that was approved. Other embassies have been more stringent from what I've read and are requiring anything from the screenshot to a certified letter from your bank as well as the statement.
Best to ask the embassy your applying to directly what their requirement is