What is there to "believe"? Precious Plastic collects and creates some knowledge, furthers the education of many people around the world and transforms some stuff that would have otherwise gone to waste to useful things. I really do not understand the mental contortions one needs to undertake to judge such things as somehow negative. Is no project that doesn't scale enough to solve all the problems in a domain worthy of undertaking?

And how is it useful or respectful to be judgemental about what other people engage in and form communities around? Is being a Football fan, an archer, a woodworker or whatever in your spare time somehow more valuable or more useful than engaging with recycling, upcycling, tinkering with machines, doing community work and all the other activities that go into a project like PP?

Distraction from what? Yes, taxing plastic/pollutants would be ideal. Designing new biodegradable synthetics would be great.

But this organisation has inarguably done good in the world. There's no need to detract from that.