Yes. I've seen recent allegations that this weekend's airport protests are "terror-tied", which is obviously false and politically-motivated on its face. There was a neverending sea of false anti-Obama material throughout the election, asserting everything from "he's a secret Muslim" to "he wants all Americans under Sharia Law", to even older widely-discredited "birther" claims. These allegations IIRC mostly originated from Breitbart News, a site still under the control of Steven Bannon (who now has the IMO dangerous conflict of sitting on the National Security Committee while running a supposed news organization). They were widely shared in multiple closed groups on Facebook with memberships in the 20-50k range.
But further than that: I've seen persistent allegations and slurs against the Jewish faith (many in pre-prepared image form), advocation of literal genocide, celebration of alleged bills that would make it legal for people to use motor vehicles to strike and kill protestors, and calls for those protesting legally and peacefully to literally be rounded up and imprisoned by police because a small group of unrelated individuals committed acts of vandalism or violence. The excuse? "If they're not stopping them, they're supporting them". These were not isolated incidents. I personally witnessed hundreds of voices repeating the latter talking point on a single local news station's Facebook page, in a single night.
The current US National Security advisor Michael Flynn allegedly accidentally retweeted one of these. According to news reports, it read "Not anymore, Jews".
Further down the abyss, speaking more to rhetorical depravity: I've watched pro-Trump posters in private Facebook groups post pictures of themselves pointing firearms at the camera in response to disagreements over fact. There was also a disturbing pattern of posters sifting through the public profiles of others for pictures – essentially peoples' family photos – altering them to appear pornographic or otherwise offensive, and then reposting them in public. One even literally offered to sell a stranger's child in to slavery, on their personal Facebook page, using a picture of them, "because that's what the Muslims would do". I saw attempts to get people fired from their job due to a Facebook political disagreement.
I really believe that there are intrinsic issues with social media that are feeding this crisis: a demand for instantaneous engagement often at the expense of even a few minutes of thought, a "real names" policy on Facebook that sabotages efforts to deflect/prohibit personal attacks in discussion groups, a comically understaffed/underresourced reporting system that I've seen people on all sides try to weaponize against those that disagree with them, algorithmic news feeds that people have voluntarily handed over their information-seeking ability to, and notifications that allow asynchronous debate to escalate into what people perceive as intrusive interruptions. Many unfortunately don't know how to turn these off, and react in anger.
It's no way to communicate and no way to live.