No.
This has been a nonsense over several months.
He is referring is flying visa exempt without an onward flight.
Most of us state something like ...
"Onward flight may be required"
Indeed many reports from travellers flying visa exempt from places such as UK, EU etc without issue and no onward flight.
And also many reports of onward ticket being asked for by airline.
In this thread I was specifically referring to short haul flights from places such as PP, Saigon etc into Bangkok.
Seems the low cost airlines eg AirAsia will require an onward flight if flying without visa or reentry permit.