This may not be an abnormal problem.
I've experienced this in several cars, most of the time, the wheels were turned in one direction or another (not nearly straight) and even parking on a hill might exponentially add to the steering components being in a bind or under tension when the vehicle was turned off.
"Tension", meaning the wheels/ steering components are trying to pull one direction or another, just enough to bind on the steering wheels locking mechanism.
Hence, you must "anti-turn" the steering wheel in order to make the key turn.
You might try turning your wheels straight (or at least straighter) and "letting go" of the steering wheel (which may let it seek out a more neutral/ relaxed position) before you turn the vehicle off.
Maybe some of the factors I've mentioned are the problem, let us know if my suggestions help the situation.
If you want a laugh and to see a similar, but stupid issue I performed long ago, see this answer (about halfway down) on WEDNESDAY, FEBRUARY 6TH, 2013 AT 2:00 AM (found at the bottom of each answer) at this link.
https://www.2carpros.com/questions/1977-jeep-cj5-ignition-trouble
The Medic
Wednesday, December 25th, 2019 AT 6:14 PM