"During the war with England [in 1812] a circumstance occured that in the end made him a most determined Abolitionist: & led him to declare, or Swear: Eternal war with Slavery. He was staying for a short time with a very gentlemanly landlord since a United States Marshall who held a slave boy near his own age very active, inteligent and good feeling; & to whom John was under considerable obligation for numerous little acts of kindness. The master made a great pet of John: brought him to table with his first company; & friends; called their attention to every little smart thing he said or did: & to the fact of his being more than a hundred miles from home with a com-pany of cattle alone; while the negro boy (who was fully if not more than his equal) was badly clothed, poorly fed; & lodged in cold weather; & beaten before his eyes with Iron Shovels or any other thing that came first to hand. This brought John to reflect on the wretched, hopeless condition, of Fatherless & Motherless slave children: for such children have neither Fathers or Mothers to protect, & provide for them. He sometimes would raise the question is God their Father? . . ." (From a letter John Brown wrote to 13 year old boy named Harry Stearns, he's referring to himself in the 3rd person)
Having not watched the cushvlog but having watched the first episode of Good Lord Bird, I'd say the show less portrays John Brown as crazy for wanting racial equality, and more as portraying him as crazy because he agitated for civil war. The show's ethos seems to be equality=good, violence=bad. In the show all the slaves just want to take the first caravan north and get the fuck out of dodge, but John wants to go around fighting slaver militias. It's fine to believe in equality, but I think the show thinks it's not fine to fight for it with violence. It's okay to free slaves, it's not okay to kill slavers.
Which is a lib take. Clearly the show thinks John Brown should've just been part of the underground railroad but what was he supposed to do? Smuggle all three million slaves north on his own? Agitating for war is the only sane way if your goal is freedom from slavery and racial equality, and John clearly read the currents correctly as the country had been on the brink of civil war for years.
Militia's battling in Kansas or an armed slave revolt in Virginia could've sparked the war just as easily as Fort Sumter or secession or Lincoln's election or whatever it was that finally kicked off the war.