Comment by yellowstuff

I believe that Happy Days started the trend in the 70s, with Mr. Cunningham being portrayed more realistically than earlier TV fathers. Allegedly (I can't find a source) an executive said "He doesn't look like a father. He looks like my father."

https://allthetropes.org/wiki/Bumbling_Dad

However, in the 80s there were still examples of mostly competent fathers, like The Cosby Show and Family Ties.