"Natural" isn't really the main thing. Whether you make something synthetically or extract it from a plant doesn't tell you if it's toxic or not. There are plenty of non-toxic synthetic substances and toxic plants. And synthetic things are usually cheaper to make.

What we need is less toxic synthetics.

"natural latex rubber"

Worldwide switch-over will destroy forest ecosystems in Malaysia, Indonesia and Africa and more to replace it with Rubber tree plantations.

Did you read the links I posted? They can be made from dandelions. More info can be found in this previous thread:

https://news.ycombinator.com/item?id=37727040

Personally I would love to see a world of 100% transit, bicycles, walking, etc., but let’s be realistic. As long as we’ve got cars, we might as well try to do as much as we can to reduce the amount of pollution they generate.

In previous thread, I made same comment and got same response. So maybe time to stop worrying about forests and look into my memory.

This also solves nothing. Just switching the rubber supply from one plant to another. And recycling some old tires in the process.

The heavy metals and other particles that pollute from tires are all still there.

It's hard to imagine supply scaling with demand, or the tires providing as much grip and safety. I'm supportive, but I see no world where this is adopted.

Here is a comment thread on HN from a while back with more info:

https://news.ycombinator.com/item?id=37727040

It really doesn’t sound all that infeasible, just would require some investment to build momentum.