Can you imagine what the races would look like if the Republicans had centrist candidates like in the 2016 presidential primaries?
I don't think that it is at all certain (and maybe not even probable) that centrist candidates would be doing better. A more important factor is a candidate's political skills.
To use AZ for example, Kari Lake, who is more "MAGA" than the Senate candidate Blake Masters. Yet Lake is up 10 points, while Masters is struggling. Why? I think the answer is political skills (of the candidates and their opponents).
PA is another example. Oz was the most "centrist" candidate in the primary, but is still behind in the polls, and is only that close because of Fetterman's stroke. Mastriano is doing 5 points worse, but that can be ascribed to political skill as well.
Meanwhile, Zeldin and Levy (CT Senate) both were the MAGA candidates in the primary, and are competitive in races that no one dreamed of.