I found the same wording in all English language news. Didn't bother to look up the original in Thai. Apart from those countries mentioned, it's pretty unspecific.Visitors from at least 10 countries including the United Kingdom, Singapore, Germany, China and the United States will be exempted from quarantine on arrival, Prayuth said in a televised speech.
As before, I will wait and see what actually comes out of this announcement. And I hope no quarantine means no hotel booking necessary means no more COE. I'm ready to go on a few days' notice, provided Cambodia is among the countries exempt from quarantine and COE is abolished and good connections (flight or even better land border open).