Waiting during firing mode does gradually increase steadiness. Just waiting in place without pressing f first won’t. As I recall, moving and running will reset your steadiness, or slowly get it back to default if you’re feeling the effects of recoil.
Anyways, tried the firing on the recent version. Random character, no gun skills to speak of, then debugged a rifle and a revolver. There’s definitely a drop in accuracy, though it’s still manageable. Careful and precise aim takes too long at no skill; from one end of an evac shelter basement to another a zombie can get close enough to attack and interfere with aiming. Just firing is too inaccurate, but the simple aim and fire can still do damage.
And again at no skill hitting something at more than 10 tiles away can miss, but not all the time.
In comparison, my current non-test run survivor with high guns and marksmanship skills can still kill a ton of zombies easily. 30-40 tiles away deals consistent high damage. Hitting things at max range is very inaccurate, though. On the other hand, this’ll allow my survivor to reach the level 20 marksmanship skill if she keeps spamming bullets at targets 60 tiles away.