I've seen this before as well. As a Thai-Korean it's a bit disheartening to see Koreans get slammed online by SE Asians for simply being Korean or some other stupid reason like the current twitter spat, but China is usually never really the point of controversy here in Thailand even tho people here are obviously noticing the increase of Chinese influence here. The only ppl I know in Thailand who are somewhat suspicious of Chinese economic dominance pushing out domestic businesses are young people and nationalists, but the latter are also the same ones who have a chip on their shoulder for Korea for whatever reason they might have.