I would agree with both bolded comments, and yet both breeds are intended to do pretty much the same job!
The stance he's in to srart with. His front legs are not at a 90 degree angle they are too far forward, his near rear leg the pastern is not at a 90 degree angle from the hock it is too far back & because he is rocking horsed to give him balance the other foot has to come too far forward. Having said that he has the makings of a lovely dog, in my opinion, if he moves well. As a breed show judge for over 50 years I'd certainly give him a second look if he came under me.
I know it is difficult to really comment on a dog from one snapshot but - wow - that GSD on the move looks like a hyena in the first shot
Dog in first picture does not look as though it is on the move. more as if its moving from stance but it has a high tail set a poor croup angle & a dip behind the wither. Unless its just a shot giving a very false view I would not have thought he would do well under a breed specialist.
...it's interesting to compare the original GSD to both the Germanic and English types being currently bred .. here's Hektor Von Schwaben - DOB 1898 he looks nothing like the modern day counterparts but uncannily like the present day BSD !
I stroked a hyena once, they feel remarkably like GSDs too, as do lions! Interesting GSD founder photo Bijou, definitely more in common with modern day BSDs than GSDs, which says something for the form-to-fit function of the BSDs. Also supports the fact that that two breeds were breed for the same job/function, presumably hence very similar original forms, despite different breeding.
Striped, if I remember rightly. Someone I knew then was working in a zoo abroad at the time. The hyenas were (just) strokable through the wire but you couldn't go in with them I also got to stroke a rhino, a giraffe and porcupine! The lion was a Longleat cub who came on a school visit, an even longer time ago.
don't have pics on this computer of the tiger and bear, but I did stroke a Giraffe recently in Florida.....