The positive rate on arrival of travelers from some origins were very high (up to 17%) a few weeks ago. Since then the pre-departure test is seen as not reliable by some Thai authorities. They don‘t care, that people from most of the countries (i.e. Russia) with that high numbers don‘t travel anymore. They also prefer to have the testing business in Thailand to having it in the countries of origin.

On the other hand without the need of a pre-departure test the positive rate on arrival will go up as the number in many Western countries are high and there will always be a lot of people who are inexperienced enough to travel to Thailand without getting tested before departure. And Thailand hasn‘t enough resources for PCR testing many more travelers.

I‘m quite sure, that they will change the test on arrival to an ATK test or that they will scrap it in the next months. And everyone who travels to Thailand should have an ATK test before departure as long as there are tests after arrival.