They went for jokes, and they disrespected J/H, their six years of history on the show, and their fans.
And had J/H been together during S8 with the S8 showrunners and writers, their relationship would've been written even worse, so there was no way to win in that season.
But at least when we did get good character development between J/H during seasons 6 and 7, it tended to be very good. The car show episode gave us a lot of shippy
gifts character details about their relationship.