Honestly, I think there's some pretty sound data which suggests the sixth party system has been over for a while, if you define it as starting in 1968. I like to think of 1968 to 1988 as an "era", and 1992 to present as another era. Others consider 68 to 88 as a "dealignment period" before the sixth era, which started in 1992. The really woke people (and Wikipedia) think the sixth era started in 1968 and still continues today. We might have a better idea in twenty years.
I think the period between 1992-1994 is likely when we entered a seventh party system. One based on urban vs rural. As much as people like to talk about 2016 it was really 1992 when Democrat flipped suburban counties like Ventura, Bucks, and Westchester. 1994 was when Republicans started eating in to Democratic rural areas specifically in Appalachia and white voters in the black belt region.