[mrob]

We already make many things from materials that can be degraded by microbes (wood, cotton, leather, etc.). They can be preserved by keeping them dry, or with paint or other surface treatments. For the rare circumstances where this is impossible (e.g. medical devices) we have fluoropolymers, which I'm confident aren't going to get degraded by microbes any time soon.

[dejj]

A long time ago, wood (Lignin) wasn’t biodegradable. Trees just piled up instead of rotting. That resulted in oil deposits. These we turn into plastics.

Bacteria acquiring genes to feed on plastics would lead to closing the circle again. Although supply will be cut short when humanity gives up producing plastics.

[wcoenen]

> Trees just piled up instead of rotting. That resulted in oil deposits.

That resulted in coal deposits of the Carboniferous. Not oil.