Very little. They started offering electric seats in 18, I think the back up camera was standardized then. As was the auxiliary electric heater, for 17 I think. Also the tow hitch was upgraded from 4950 to 5000 one of those years. They are pretty interchangeable.
In 2019 they added a connection for a trailer brake controller in the tow package (Q24). There are work-arounds for earlier years, but if you are planning to do any towing, get one with the factory tow package.