I know that i wasn’t supposed to do this but i changed to a 70mm,from a 110, stem and wider bars on my road bike.
I haven’t careered downhill or around bends out of control,in fact the steering feels more precise.
I don’t do racing or time trialing so aerodynamics are secondary compared to comfort.
No more back,shoulder or
I went from a 120mm stem with 400mm deep drops to 60mm stem with 440mm compact drops, that was~3 years ago and made the bike comfortable for an MTBist new to road bikes, then a couple of months ago I adjusted that setup by fitting an 80mm stem and flipping it.
With time spent on the bike I think I have gained a bit more flexibility, and the bike needed to change again, the stock position just didn’t suit my mountain bikers physique, it can always be adjusted, and over time your body will adapt and a bit of readjustment is acceptable IMO. We’re not all natural born racing snakes…