Lai lai, be my guest..I always welcome constructive criticism, it can help me sharpen my rational thinking skills and see things from a perspective I can’t due to confirmation bias..
I’ve thought through all the above concerns you have, fortunately I’m able to address your concerns in simple words, as I’ve watched the zoom meeting given by the Alvin Ang back in Oct 2020.
1.) according to Alvin ang, world plastic demand is growing about 5% annually, slowly but steadily.
2.) TGuan has bought in additional resins when the price was low last year, so it won’t affect their QR in coming 2 quarters if I remember correctly...their nanotech in the premium stretch firm sectors allows them to command higher profit margin (the new factory started operation since late Oct-Nov last year, with additional 11 production lines, each line can pull in 100-500 mil annually, Alvin calls it the “next billion of their revenue”.
3.) they saw this coming, so their PPE are transacted in USD for hedging purpose.
4.) internationally speaking, they have started expanding their stretch firm production to Myanmar..domestically, more factories are built to increase production lines, and with the increasing courier bag demand, they have allocated new factories to accommodate..
If you have time you can search on fb the video below under cgs-cimb page, I sourced my explanation from the meeting

So yeah tguan / scientex no brainer. Just buy and sit on it, wait for packaging boom. It will come, especially now most big brands will switch from corrugated box to eco friendly plastic packaging due to its flexibility and weight.
Also also don't forget the amount of ecommerce transacted currently, do you notice all your goods from online come with some form of plastic packaging such as shrink wrap or some bubble wrap ?