Every generation has some product/ingredient that they didn’t know was dangerous at the time: tobacco, lead, asbestos, etc. What is that item for this generation?
Microplastics are the new lead, and screens are the new tobacco, in my opinion. Overuse of sugar in processed foods is the new version of how they'd cut food with inedible stuff like sawdust back in the day.
My mom become an avid anti-plastic person after watching videos and reading things about the damages that microplastics do to the health, nature and the planet. She does everything she can to avoid using plastic things!
When plastics were first introduced to consumers it was sold as indestructible, it will never wear out, never degrade! People were actually concerned at the time, why anyone buy disposable products that never break down, won't they just pile up forever?
After much lobbying the concept of recycling plastics was introduced to help consumers stop worrying about all this indestructible waste and help push the sales of cheap plastic products. Your mom has the right idea, not buying it in the first place is the only way to drive demand down.
Try to stop using disposable plastic as far as possible. No cups, bags, spoons, straws. Use reusable bags when shopping, and when shopping, check how the stuff is packaged. Get as much as possible of your stuff in glass bottles, and recycle them. Use waxcloth instead of plastic wrap. Buy larger packages. If you have a cheese or meat counter, get your stuff there. The might even let you bring your own tupperware.
The problem with waxcloth is you can't clean it well enough, because no hot water. If I can't use it on meat or dairy it's no good for me. Also I can never get it to stay, maybe because I have cold hands. Reusable lidded takeout containers work for most food storage and go in the dishwasher, until they finally fall apart and get recycled. At least it's better than using cling wrap.