This is a non result. Of course picking singular stocks yourself with little understanding of the financial market or the companies in question is a terrible idea. The real question is: Does this approach perform better than a maximally diversified index fund?
I read the article as a "just buy a low cost whole market index" - which seems to be the most common advice out there.
Assuming your randomness generator was fair and you bought enough stocks, your 'buy stocks at random' strategy, if you bought enough stocks, would eventually get you that maximally diversified index fund, I think?
I mean, I think the difference at scale is all in the weighting; if you bought one share of a random ticker on every throw of your random generator, you'd be overweight stocks with high per-share values vs. just buying, say, a basket of VTX, VXUS and VWO, which are weighted in more reasonable ways.
