For perspective, the acquisition was before IG had ads and before Facebook was publicly traded. How was the FTC supposed to magically see the future anti-competitive actions (like blocking vine)?
That same perspective shows that the industry has evolved since then. If FTC can't be held accountable for not predicting the future neither can Facebook. Of course, I don't believe this at all since anyone in the industry knew exactly why Facebook would buy Instagram, especially the FTC.
Are we not holding the government to a higher standard than private companies now or what? The FTC's entire job is to do these types of analyses. It's unfortunate that we're so used to the government being dismally incompetent in every way.