Is it still possible for Republicans to win NYC mayor?

[Arizona Iced Tea]

In the 1990's New York City was ruled by mayor Rudy Giuliani despite the city being solidly Dem federally. Following the September 11 terrorist attacks that left a dark mark on the city, Bloomberg managed to keep the mayorship in Republican hands for the rest of the 2000's before switching to Independent in 2009. However in 2013 Bill de Blasio easily won the mayoral race and it has stayed in Dem hands ever since. Obviously a MAGA Republican can't win it back, but could a moderate Republican with a unique background be able to flip it back?

Bonus: Why does NYC seem to be more friendly to Republican candidates than LA or Chicago?

[Arizona Iced Tea]

In the 1990's New York City was ruled by mayor Rudy Giuliani despite the city being solidly Dem federally. ... Obviously a MAGA Republican can't win it back...

As to your last question, there was a lengthy discussion on this recently that you can find via search.

I remember reading something about that on here, but I couldn't seem to find it on the atlas search. A link would be helpful if you can provide one.