Good vinyl can have as much as 70dB dynamic range on the outer edge.
Its easily higher than that (I run an LP mastering operation); but compression and tape are often the reasons why you don't see that in practice.
Direct to disc recordings will not solve playback problems, one of the reasons why it was virtually abandoned.
Nothing solves playback problems on the record side :)
The reason you don't see much in the way of direct to disk is simply because its really hard to do! Musicians have to play all the tracks on a side perfectly and that's assuming you don't overcut because a performer is playing 10db louder in record than he was when the levels were set!
So its a bit of a trick but when it all comes together its magic.