As for the collectability, promo production numbers might be one facet, but I'd also suggest a couple of other issues:
- Limited awareness of the set
- Limited appeal of the design/humor
Pro Set cancelled the project because the Players Association wasn't happy about it:
https://www.chicagotribune.com/news/...410-story.html
Flopps has an interesting story.
Like mentioned above, it's the predecessor of the 1993 Cardtoons, which chose to defy the Players Association. The MLBPA then sued to stop production, but ultimately lost.
By 1992, a generation had grown up with Garbage Pail Kids, and many knew MAD Magazine. That year also had Baseball Enquirer cards, nameless caricatures with mock interviews on the backs, and the Spoof Bogus Baseball Cards with Tony Goon and Swollen Cryin. Still, I'd have to imagine that Flopps would have stood above those, being produced by a mainstream sports card company.
In the lineage of these spoof cards, you could connect to something like Wacky Packages, but what previous cards satirized actual players/teams?
Laughlin cards were more tame but might qualify. I have a couple 1975 Laughlin Batty Baseball cards, a set featuring the likes of the Milwaukee Boozers, Houston Disastros, and LA Smoggers.