Thanks for sharing your first-hand account of diving in Thailand. I think they should aggressively pursue coral planting. They are several projects in Indonesia that have demonstrated excellent results. I volunteered for a day doing coral planting in Bali, Indonesia. As part of the dive, they take you to different parts of the coral reef as it recovers, showing you how it changes year after year. You can see the change with your own eyes.

I agree though we had very mid results here in the Gulf of Thailand while the Andaman Sea side has had more luck. The issue with Gulf of Thailand is that it's just so shallow with avg depth of only 50m and too calm making new coral growth very hard with existing techniques. There's some new promising research on alternative methods of raising coral larva in labs, but I'm not up to speed with that yet and it seems quite complex.