This highlights that military organizations have changed, but armor design hasn’t changed that drastically, for a simple reason, its purpose has remained the same since people went to war armed.
Since human morphology hasn’t changed noticeably since antiquity, you still need to protect the same body parts. Threats evolve (from antique weaponry to modern warfare) and new materials are used, but priorities remain the same (ie. you’re likely to worry about your soldier’s head before their left ring finger)
Same thing about rifle’s pull. It still depends on the average man’s arm length.
Bear in mind that I don’t overly care about ultra realistic weapon design, and won’t cancel my pre-order if the sidearm’s grip is angled to sharply to let the magazine feed the chamber properly, but it does pass the time on these forums. @Kings_Rook’s feedback could also be valuable for the artist who drew this should he wish to read it.
Lastly, as previous XCOM’s have graced us with weapons such as the Devastator Cannon (XCOM:Apocalypse) that looks like a somewhat hairy swine’s snout, I’d say everything is possible.
(Thankfully, that was an alien design, but if the entropy launcher’s marked me forever by its sheer nastiness in game, the sheer hairiness of the devastator gun has been imprinted so deeply in my brain that I don’t think I will ever forget it_