You've got that right.
The government had workgroups and committees trying to get the tourist tax incorporated into the ticket price but there was no way IATA could do it the way the tax was conceived.
Luckily, and this being Thailand surprisingly, they had the good sense not to go for collection of the tax individually and in cash in Thai currency from arriving foreign passengers subject to the tax.
The manner in which the PM announced the abandonment of this scheme is a face-saving way to bow out of it.