Not everything can be or needs to be biodegradable.
We don’t need biodegradable houses. The wires we use in all of our electronics can’t be biodegradable.
But- we can find ways to recycle those materials.
So I would say that the thing to say is that biodegradable or recyclable everything is usually better. Even then, though, some things don’t fit those categories. There are all sorts of medical things that get implanted in human bodies (stents, for example) that can’t be biodegradable and also won’t be recycled unless we really change the way we think of our dead relatives.