You know you would have thought all the years and years of "donations" to "cancer research" there would be constant news stories about how we accidentally cured a bunch of ancillary medical problems, and wow its all free to everyone because it was from donations!
Even without that I'm not sure why you think that's a good point — it's very easy to find serendipitous examples in medicine in general, e.g. viragra which was initially a heart treatment, or even thalidomide whose anti-cancer uses were suggested by the very birth defects that made it infamous.
Specifically cancer research finding other things by accident:
Was there any "productionization" of the "cure" for baldness & gray hair, after it was discovered 7 years ago? I reckon, there's a huge market for that cure.
I mean I get this is a joke, but it's still homophobic at its core, imo. Why riff on the same on argument against homosexuality when it would've been much more humorous to "turn it around" and joke about finding a cure for heterosexuality and research indicating that homosexuality should be the de facto state.
Tho tbf when I've joked about that with str8 friends they get really upsetti spaghetti, yet somehow still can't link their spaghettiness to why I was offended when they said "just don't act gay" when I said I would love to see Egypt but didn't want to travel there.
No need to treat research like a business.