There's no guarantee that Nintendo won't make more NES cartridges either.
We've seen the likes of Data East, Capcom, and even Irem remake their games and re-releasing them these past few years. And I personally consider them in the "Unlicensed" umbrella since they're not approved by Nintendo.
In the early '90s Activision released a whole bunch of their NES games in Brazil. Only, they didn't seek Nintendo's permission and they're unlicensed. Perfectly legitimate games, but entirely unlicensed.
Speaking of Brazil, they have an entire eco-system of grey-area to completely black market bootleg games that people are 100% nostalgic for the same way you and I are nostalgic over Mario, Zelda, and Mega Man.
I promise you, this video is worth a watch:
It's easy to just omit Brazil from a list.
But when you see actual people in an actual place looking at their bootlegs like how we look at our licensed games, you sort of realize that everything matters.