well you might think of it that way since you have a point.
but let's just say ending the story of TLOS that way is the best thing that could ever happen. yeah, you could say that they could have been happier if they ended up being together. but did it happen in real life? haha.
where am i getting to? well, this may shock you a bit but TLOS is an autobiographical movie of chookiat sakveerakul. that's right. the real life mew is ying's brother. he's the director, producer and music maker of the TLOS movie. not to mention he acted too. haha. chookie's first name is matthew. remove the letters "atth" and you get mew. i don't know where tong came from though.
so i guess, the ending of the TLOS movie is the exact event that happened to chookie. mew and tong didn't end up being together, yet the movie is open-ended. so we can't really tell what happened afterwards. my hunch tells me that they never became lovers. but you can believe anything that you like. hahaha.
the speculation that maybe they are embarrassed about making a sequel can be true. in my case, i believe that TLOS is the main cause of the popularity of witwisit hiranyawongkul and mario maurer. (pchy didn't get that popular in dopamine, and i think mario wouldn't be discovered if not for TLOS) so it really wouldn't hurt making a sequel out of it. but they show respect in chookie's decision not to make a second part. (politeness is very very important to thai people.)
gay people maybe still be discriminated all around the world. and chookie wanted to change that. basing from the awards that he received for making an outstanding movie, we can say that he has achieved his goal. you yourself is an evidence of that success, because you liked the chemistry of pchy and mario in the movie.
now, pchy and the august band is very popular in thailand, even in their neighbor countries such as china. mario has been working as an actor and model at thailand too.
in the end, i would like to say that having a gay role is just a part of work. it's not about the things people will think about afterwards. it's about how realistic your acting would be in the big screen. pchy and mario are actors. so basically they have to do whatever the directors tell them to. haha.
well that was long. i was really hyped up wasn't i? hahaha. thanks for bringing this thing up. it got my brain working. +1 to this thread!