WieWaldi With one big difference, making your statement an apples and oranges thing:
The C position does not allow to play all music. There is no other way around than leaving this comfort zone.
The need to use sometimes the bass clef for RH and vice versa is a convention. There are multiple alternatives - they all work - and some of them are even easier to learn.
The point is that music doesn't always stay in C position with D played with finger 2: Music isn't always written with treble clef for the RH, bass clef for the LH. In both cases, if you learn in a restrictive manner, it will become difficult to play the music that is out there.
Reading can be taught in a manner that makes things difficult to learn. Shortcuts for "quick progress" in the beginning can become a handicap later on. I've seen small children learn to navigate among the clefs because of how they were taught. Music in a clef denote locations on the keyboard. Would you have trouble locating your kitchen if you stepped into it with your left foot instead of your right? The kitchen is still where it is. The piano key that is two octaves to the left or right of middle C is still in the same place regardless of which hand or finger you choose to go there. If you were taught LH = treble, RH = bass, then you've been handed a handicap.