I believe that people are conflating two different events happening at a similar time, the Chinese scammers and mobile security confirmation which WILL result in non verified accounts being closed...
According a report from a visa agent, internal BKK bank regulations currently prohibit opening accounts on tourist visas because of regulatory issues, but there is no actual legal prohibition (i.e. they're not prima facie illegal). There are issues with accounts which don't match registered mobile numbers etc. but that's a general regulatory issue, not one specific to tourist visas