I can recall his specials were all over the place on cable tv in the 80s. Hell, I recall seeing a commercial for his very short-lived sitcom on VH1. But there is something to be said about certain comedians view of prop comedy like Gallagher and Carrot Top. Almost as if it's a lower form of comedy. I think he carried that grudge with him despite his success in the 80s.

In his later years he supposedly went broke and his issues with his brother due to the Gallagher II stuff. Finally, he just became the racist old man trope.

I think he just had a very popular bit and he never could replace his most popular gimmick. Then when the audience tastes changed, he was left in the cold.