If I believe the news, 75% of the French are infected with the English variant. That's why France reopened their borders with the UK, because the English variant is not considered a variant anymore but became the "standard" virus.
from 1987 to 2002, the rule already existed but nobody was ever asked to report. Then a smart guy decided to enforce that old law from the communist guerrilla era.
I got a 15 days "under consideration" stamp last time I applied, but the officer told me to come back the day after to get my full extension. The reason was that the signing officer was gone to Bangkok for a meeting.
Everybody need a COE since August 2020. Doesn't matter if you're coming with or without visa, you'll need a COE for people at Bangkok airport to prepare for your arrival.