Gambling becoming increasingly legal is a problem. It's leading to some very unhealthy addictions for the most vulnerable and those that can least afford it. Ironically, it's likely some startups lobbying contributed to the changing landscape. (sports betting startups)
Same idea that keeps games like Candy Crush afloat... 1% of the users account for 99% of the revenue (napkin math)
There are more people treating "investing" as a form of gambling or short term game they can play to get ahead. For example, they engage in chart patterns, options, shorting, and day trading. Think WallStreetBets, GameStop, AMC
As far as the odds of breaking even or doubling your money- who knows?
I think the other point is: if you're not wealthy and you lose a large sum, it has a huge impact, maybe destitution. If you are wealthy and you lose the same large sum, it won't matter so much to you. Investment isn't generally in $5 or $10 amounts. (Maybe there's an investment model available, but that's where the scammers prey.)
And direct startup investing ain't no Field of Dreams fantasy. The vast majority of startups fail. Plus - large-scale scamming operations exist, and average Joe's are often easy prey.