Objectively false statement.
This is pure opinion with zero basis in the game. And there is evidence Joel isn't the most skilled or most powerful.
For example:
Marlene managed to take the same journey Joel and Ellie did and we don't know exactly how many other fireflies she had with her.
Bill basically lives by himself out in the middle of an area having an entire town rigged up to protect him.
Tommy is basically like Joel when it comes to skill and strength.
There are several enemies that are physically larger than joel.
https://www.youtube.com/watch?v=xCycerwf2Ug - "He ain't even hurt." That man clearly has a larger build than Joel does.
You even admit that Joel gets taken down by a punch, implying there ARE people physically stronger than Joel ... your own argument is self defeating.
Also, Joel survive a car accident while in the driver seat with a seat belt. Abby literally survives in a car accident while in the bed of a truck without a seat belt. If you find Joel surviving a car accident unbelievable and not grounded, than that Abby applies too.
The problem isn't that your points need refuting. The problem is you are NOT applying the same standard to Joel as you do to Abby. You will bend over backwards to make Abby seem more grounded, when she isn't and outright lie about a Joel.