Nope.
I'm typing this on a Model M that is full of cat hair, crumbs, coffee grounds, staples, ash, hardened lava, reinforced concrete, yeti droppings, and the odd bit of unidentifiable radioactive funk of extraterrestrial origin. The spacebar works smoothly and perfectly at either edge.
I've had some trouble with the shifts, but they don't have stabilizer bars, just plastic guides. I expect that this could be remedied by cleaning the keyboard more than once every 5 years, though.
I never had any spacebar trouble with any of my mechanical apple keyboards in the years past, either.