I was attempting some levity to lighten up how personally you seem to be taking this. If that gave offense then you have my sincere apology.
The point still remains that “walkability” is not the fungible criteria that you seem to believe it to be. Phoenix, like most cities, has standard gravity and is not built on a foundation of molten lava so it is naturally possible to put one foot in front of the other; however, that one can physically walk from place to place is not in and of itself evidence of good “walkability” as the term is used by urban designers. Walkability is rather a composite index of how “friendly” a city is to pedestrians (e.g. good pedestrian design), including how much protection is provided against hazard and interference by automotive traffic, how flexible walking routes are and how accessible destinations are, how comfortable the walking environment is, how well public transport facilitates walking to and from destinations too far to reasonably walk, and how well mixed a “walkable” neighborhood is in terms of shopping, schools, public spaces, and other destinations.
You are correct that US cities are not, in general, designed for pedestrians, and even those with high walkability and rideability indices are more a matter of circumstance and community action rather than systematic pedestrian/rider design. Since the post-WWII era cities have been deliberately designed around the paradigm of separate living, working, and public spaces, e.g. suburbia and reversion of that trend is a recent phenomena, and the general culture around driving has led to pedestrian needs to be largely ignored or even deliberately removed to discourage pedestrian interference with traffic flow.
But by any measure, Phoenix is a very pedestrian-unfriendly place; outside of dedicated shopping districts, stores are invariably either in strip malls or in set-alone buildings with massive parking lots in front of entrances; schools are widely spaced requiring busing or children being dropped at school; public spaces like small parks, shelters, and set-asides are rare; cycle lanes, where they even exist, are unprotected by physical curbs or traffic reduction measures; and sidewalks are often non-continuous and are directly adjacent to busy streets rather than being dedicated pedestrian paths that are offset from roadways. This is not just a subjective evaluation; it is quantified in the walkability score cited above.
You’ve used the word “hellhole” a couple times, which is not a term I have applied, but while the climate is comfortable right now in mid-winter, public health authorities routinely issue warnings about being outdoors for weeks at a time in the summer, which is a trend that is only likely to get worse. And the city and surrounding area is a kind of ecological nightmare for the misuse of water to put green lawns and golf courses in wealthy areas, which is another reason to question the long term viability of moving to Phoenix. As you have noted, the area has been subject to a mass of immigration from surrounding states which has served to overstress the already limited natural resources, which is another issue that will only get worse. You have clearly lived there for a long time and apparently it suits you well, but it doesn’t seem like the best fit for the criteria laid out by the o.p.
Stranger
I may have been a bit too harsh. I have lived in NYC for a year and didn’t find it too cold.
My grandmother was the oldest native phoenixan when still alive, and my mother was born and raised there. I went to grad school in Phoenix in 1990 during the heat wave. IIRC the low exceeded 90F for 100 days straight. The airport was shut 2 days in a row because it was 121F one day and 122F the next, and the planes didn’t have enough airlift to take off. It is not unusual to be 90F in April and go up from there.