First, Cincinnati chili is meant to be thinner than traditional chilis. I've heard it referred to as soupy. It shouldn't be too liquidy, but should be saucy. The best way I've found to thicken the chili without adding thickeners, is simply to simmer and let the chili reduce down through evaporation. If you're making this in the Instant Pot, you'll definitely want to let it reduce. Slow cooker and Dutch oven methods, won't need as much.