This whole thing is a business deal wrapped in political ideology.
There’s a long-standing FCC law that prevents the accumulation of media properties that reach in excess of 39% of all US households.
Nexstar (a media group owning and operating many ABC stations) is interested in buying another company that would result in a violation of this FCC rule. The rule exists to limit concentration of media influence.
The announcement to preempt Kimmel was a tactic to ingratiate themselves with the FCC chair so that he will make an exception to the rule. Hey, it worked for CBS (see, Colbert).
If you think the media conglomerates are already too big and have too much influence, then you should be pretty concerned about what is really going down behind all of this hand-waving about comedians.