Sinclair owns stations in Rochester, NY, St Louis and the Champaign/Urbana/Peoria/Springfield markets. Their ownership leans red, but it's more mixed than is given credit for.
Nexstar is similar, they own stations all across Upstate New York (Syracuse, Binghamton Albany), Hartford CT, and Richmond VA.
I don't see any way how this doesn't harm all of them more than Disney/ABC running Kimmel harms Disney.