Vegan leather or faux leather these days is far from your poly plastic of old. Vegan leather is breathable and made from a huge range of materials synthetic to organic. Vegan leather is a cheaper alternative and is often as comfortable and durable as leather.
That be said if you own a leather jacket it is more respect to love it and appreciate it then see it possibly go to waste.
When buying consider second-hand vintage leather or vegan leather. Respect resources, people, choose the best sources of materials, manufacturing and process. Considering using what we already have got second-hand or vintage.