Yes, I'm not saying the TypeMatrix pure grid layout is 100 % ideal, maybe there should be just a little bit of stagger to account for the angle of the wrists - but there should still be symmetry of course. I think the TypeMatrix is far superior to the standard staggered layout though, when it comes to the concerns you raise.

The standard layout is just horrible, reaching "v" and "b" with the left index finger while keeping the rest in home position requires an uncomfortable amount of stretching. Even for the right hand, I think the standard layout errs on the side of too much stagger, which is evident when using the pinky to hit the "/" key. There is certainly a lot more wrist distortion than when using the TypeMatrix - there tends to be less distance between the "a" and "l" keys on a standard keyboard as the TypeMatrix places the Enter and Backspace keys in the middle. I guess the Kinesis Advantage might be more ideal in that regard, though I don't suffer from any significant wrist distortion with the TypeMatrix. My hands tend to look like this when using it: https://ploum.net/images/tmhands.jpg

The small size of the TypeMatrix also makes it a win for me, as I occasionally bring it along with the laptop when I sit in the couch for example.

Qwerty is another inefficiency, and I use Colemak myself. The difference between a standard keyboard and the TypeMatrix is still far from negligible.