Just another thread I see where people on FT start with the presumption that they know more than the actual revenue managers :-). And guess what, you might be right some of the time... But not likely a lot of the times.
And as was mentioned there have been "sales", just a bit more subtle than lowering generic rates. Especially the better properties in BKK have a fair degree of customers that still pay the regular rates, so it's a fine line to maximise those revenues and still go for a decent occupancy rate.
It's not all tourists that decide on a destination just because of hotel rates and are flexible enough to actually go.
But if this drop in occupancy continues for a while, I'm sure they will get a bit more aggresive. And it also seems that occupancy in general isn't affected much, it's mostly BKK.