I love the show but this need to insert present day human conditions to a place 400 years in the future seems a bit ridiculous. Even today in the 21st century we are close to curing many ailments but in season 2 episode 11 they show a crew member on the Discovery going about his duties in a Wheelchair.
A Wheelchair???
I sincerely doubt there will be wheelchairs 100 years from now let alone 300-400 years from now. (For people without legs I would expect they would have bio-electronic prosthetics
We are on the way to perfecting medical cures using stem cells to regrow healthy appendages and organs. We are at the beginning of a world where nanobots can be injected into a human body to not only provide protection from injury and disease but to even heal.
My point is "There is no reason to play the "We must portray crippled and physically defective humans card" for the sake of political correctness when it's highly likely if not expected that the future will consist of humans with no physical ailments and certainly not rolling around in devices that will be no doubt considered antiquated and completely unneccesary.