Not so much "reading our minds" as just predicting our minds based on psychological profiling. If you've been following the revelations about Cambridge Analytica, you'll know that this is confirmed, but CA is far from the only application of this. It's just the one that's happened to be exposed, and is being especially criticized for helping Trump win. Yet Wikileaks is tweeting out articles, emails and videos about how the Democrats used very similar tools in 2012 and 2016 as well. The media just isn't as concerned because it's mostly pro-Democrat.

Businesses do it for marketing. The tools they use may not be quite as sophisticated, but it's the same basic idea. Collect as much data as you can about your target, then use psychological profiling to predict their needs/wants/interests/etc. Write an algorithm or two and boom... you got an automatic system for analyzing and responding to everybody's every whim.