It’s an obvious joke to point out that Friday the 13th: A New Beginning came out just 11 months after the supposed series-ending Friday the 13th: The Final Chapter.
Friday the Thirteenth: The Final Chapter has a title so inaccurate that Lionel Hutz would pursue restitution.
Though a mere two summers had passed since Friday the 13th debuted and turned slashers into the de-facto teen film of the nascent 80s, the trend was on the verge of burning out in 1982.
I am not a historian on the matter, but as far as I can tell, slasher franchises did not exist before Friday the 13th.
I find the origin story of Friday the 13th to be poetic.