Every time there is an incident like the Myanmar one tge authorities panic, and today they acknowledged people crossing from Cambodia illegally even I know people who used to do that pre Covid19 have you seen the Laos border,the Meking is hard to police.
Not really no one knows how good the vaccine will be, how the virus is going to mutate, the one in Myanmar us more infectious than the Wuhan one and the Thai government is hyper careful, too many variables to ponder.