Donald Trump won the 2016 election and Republicans did very well down the ticket that year. Since, then, however, the GOP has consistently underperformed in every election since then. It is obvious that Trump has a negative impact on candidates who are running outside of deep red districts.
While Kilmeade may be desperate to spin, Trump is a major problem for the GOP right now. He is leading primary polling by a massive margin. As the standard bearer for the Republican party, this recent election season was very much a moratorium on him.