King Of The Hill was canceled for this?

King Of The Hill was canceled for this?

No, it wasn't.
FOX purchased the Cleveland idea in 2008. They had planned on cancelling King of the Hill after its 10th season in 2006 but changed their minds (obviously).

FOX had toyed with the idea of ending the series more than once apparently according to Mike Judge, “We've had so many false stops along the way when I thought the show was canceled, the end now doesn't have that [momentous] feeling.”

Also, it should be noted that Mike Judge didn't seem to mind ending the show, “And because there was a point when I thought I didn't want to do it anymore.” “I actually think it's probably a good time to stop.”.

Now it's reasonable to assume the final decision on cancellation was probably made when FOX decided to give T.C.S. the time slot, but since they had been thinking about it for 2 years prior... no, there was no direct cause and effect. It wasn't cancelled because of The Cleveland Show.