Back in the 80s I remember a lot of talk about using starch while making plastic bags to make the bags break up. Then it was thought of as a good thing, before we knew about the effects of micro plastics. If the whole thing can be composted, food waste recycling is going to look very different when you can throw out the takeaway container as well as last night curry.
I guess really, it should be 'biodegradable alternatives to plastic'. One of the first used (developed commercially in the 80s by ICI, later sold to a US company Monsanto) is polyhydroxybutyrate. It comes from bacteria (e.g. Ralstonia sp.) originally. They use it for energy storage (a bit like we use fat). One of the earliest applications was for surgical implants.