I flew from New York to Kansas City last month, and the departure and arrival times only varied by one and a half hours. That time zone change is huge.

I took a flight last year from Chicago to Philadelphia, I was surprised the flight wasn't even an hour long, although it was scheduled to be longer, I think approx 2hrs.

Well no as there is a 1 hour time difference so I believe e at anything more that the deptuare time was 6:00 PM (eastern time) and 6:45 (central time) which would be 1 hour and 45 minutes, should nothing that goes wrong like the airplane crashing that would delay it. And he didn't even count on the flight being delayed.

I just saw the question "NY to Chicago in 45 minutes?", so thought the OP was asking was the trip only 45 mins.
I thought that's what he was asking

To tell you the truth, I did not even look into that, I just saw the question "NY to Chicago in 45 minutes?", so thought the OP was asking was the trip only 45 mins.
But as you have pointed out, this appears to be quite a goof.

Even with the time change it's an unrealistic arrival time. If you check a JFK-ORD non-stop flight it generally takes around 2:45 heading west, which means they should have arrived at 7:45 local time, not 6:45.

I am guessing time zones come into play here.