I've surmized that mercury lighting is nearly non-existant in most of Arizona which includes Phoenix. But does Phoenix have LPS street-lights like Tucson does?

I don't recall seeing LPS in Phoenix.  You won't find much MV in metro Arizona but may find some out on ranches and in the country.  (or desert)

Saw a few mercury outdoor lights in the Phoenix area, mostly older commercial buildings. Otherwise not much left, there are plenty of 1960s cobra heads in strip malls that have been converted to metal halide.

I was born and raised in Phoenix.

And I can tell you with certainty that the Phoenix metro area never had LPS street lighting.

Very rarely, you'd see a business had LPS in the back alley. And at the boat ramps, you'd sometimes see solar powered LPS.

I would go to California as a kid and absolutely be fascinated with their big 180w LPS lights and their Econolite neon ped signals with the emerald green "WALK" neon. Always a treat for me to visit California.

I also remember 3 phases of lighting on my street. We had the incandescent gumball, which was swapped over to a MV NEMA bucket, then later a typical 100w HPS cobrahead. I'm only 40 years old, but I got to see all 3 types of lighting deployed in my neighborhood as a kid.

Thank you for this info.
I'm older than 40 but never remember incandescent street-lighting in my city.