Opinion columnist Barth Keck says we shouldn't expect any substantive solutions to the misinformation problem from social-media platforms, especially when it comes to political information. As the election season gears up, emotionally-charged, fact-challenged posts – the very content that attracts the most clicks – will only increase. The Facebooks, Instagrams, and TikToks of the digital world aren’t likely to put a stop to those cash cows.