The issue is time scales. Plastics take thousands of years to degrade but we only really use plastic products for a few years. What can we find that hits a sweet spot of, say, 10 years? Wood does this well, and it’s mostly cellulose. So is paper and this stuff.

If people are going to manufacture trash that breaks or become oBsOlEtE after a year anyway, you might as well have it biodegrade when it's done.

It's not, but the planned obsolescence advocates sure love it, since they can make products self-destruct and eco-virtue-signal at the same time.

Depends on what you want.

Disposable cups, plates, forks, spoons, etc? Sure... eat whatever was in them, throw them wherever, and they'll rot very fast.

Electronics.. mostly not. Maybe some light-up bracelets for a festival, but those also contain batteries and LEDs, but it's still better if at least the strap degrades and rot.

Lots of electronics are waterproofed as well. I doubt that biodegradation would happen very quickly inside a modern smartphone chassis