Yes, Jefferson had a relationship with a slave and had children with her, but we are unsure what the exact nature of this relationship as neither is around to talk so using it as a cudgel against him isn't entirely a fair thing to do and yes he didn't free his slave children while he was alive, but we aren't sure of his reasoning behind that decision either.
IIRC, this is not actually true.
A Jefferson had children with a slave, but it was not
Thomas Jefferson. The popularization of this idea was just an attack on Jefferson from decades ago, popularized in media and with a TV show.
Further, it wasn't just political suicide for many of the Founding Fathers to free their slaves, it was
flat out illegal. It was something the law in various states forbade outright. In Virginia, IIRC, they managed to get a loophole in to free some slaves upon the death of the owner, if it was put in the will, which George Washington and others did, but even
that was not possible in all states.
In their writings, many of the Founding Fathers made it clear that they expected to manage to eliminate slavery within the next fifty years through sheer economic pressure, it wasn't profitable or competitive. The reason the Cotton Gin is so important historically, is because it made slavery much more profitable than it had been. And ironically enough, there was widespread patent fraud by southern plantation owners and the like, who would have blacks working the machines in windowless buildings, and because blacks couldn't testify in court, proof of infringement couldn't be had. Eli Whitney moved to the North and was successful there; the South drove him (and other innovators) out with their moral perfidy.
Also, in regards to people being worried about his escalating into a full-up civil war:
Remember that the CHAZ is happening in what is
already an overwhelmingly leftist-dominated city. The overwhelming majority of the
riots have been taking place in leftist-dominated cities. If this shit starts spreading through conservative areas,
then I would start being worried.