Game makers are still catering to previous gens as well as current. This typically helps to make more money while people are still adopting and upgrading. If only 10% are on me hardware the first year, no sense in doing all the work for a few to enjoy with major losses financially.

Until they let go of previous ones and focus solely on new, also by developing new in-game engines, etc, it won't improve. This is how it always is.