Worse than 2015? Hell no, not even close.
This season gets a 6.5 IMO. I think the main issue was with the short tracks not being the best. If, they can address the short tracks, I think the product will improve. Also, Michigan/Pocono/Indy all tracks over 1.5 need to be addressed.
The best racing IMO, the plate package was pretty good tbh. Daytona and Dega were pretty solid races, NASCAR needs to find a happy medium with all of the tracks. This year had potential, but the lack of power at the larger superspeedways and to an extent at intermediates need to be solved. It wasn't bad, but more power could be helpful for them.
I sure as hell have no answers, but this season is miles better than 2015 and 2016. Pales behind 13, 17, and 18. All Gen 6 years, its probably the fourth best year.