Yes, it's a pity, I traveled to Quan Lan Island in 2010, my wife and I thought it would be unspoiled and off track. But the boat there was full of people throwing litter over board, I even saw a lady pull a diaper of a child and throw it overboard without even thinking. The beaches were littered with colorful plastic. (I have a picture on my Nextcloud but no idea how to share it and my wife is very prominent in so I won't but the picture still make me feel sad. Edit, uploaded but only downloadable for 7 days or 100 times apparently (and cropped my wife out): [0])

I also got the feeling that small bays that were labelled as nice in our perhaps a bit dated travel guide were filled with large hotels between the time since they were labeled as such and when we arrived.

Overall though I found Vietnam very, very beautiful indeed and the people were very kind as well (outside the tourist industry at least).

I guess it's an education thing, as kid I constantly heard in school: Plastic stays around for 2500 years! Birds choke on your chewing gum! The hole in the ozone layer is our fault! TBH I felt pretty burdened, sad and responsible by/for it, but I guess it has its advantages.

[0] https://send.firefox.com/download/c48c1add8b2d74a0/#qxQ-qoh-...