Is it not the same for guitars?
Absolutely, same rules apply.
The other day I had a brand new Ovation in my hands that played like absolute crap.
There was no way I could ever play it on stage if I had to.
I messed with the truss rod, put new Martin 10 strings on it and it plays like a dream.
The owner felt the difference straightaway and I know he's the type that will improve now its easier to play on.
I wouldn't have thought you could 'set up' a sax like you can a cheap guitar.
I have a really good collection of top guitars but the best one is a £200 Variax that my mate set up for me.
A really well setup cheap guitar can feel just as good as an expensive guitar and of course the better the feel the better you will be likely to improve.
Just to re-iterate my OP before somebody comes along and completely twists it.
1 - You walk in a pub and see fantastic equipment.
2 - You immediately think that these guys must be good because of the many years you've witnessed gear/talent.
3 - They go on and they can't put 2 notes together.
4 - I think "What the hell are they doing with gear like that?"
Of course, anybody can buy whatever they like but sometimes things don't go together.
It would be like me buying a Ferrari to go 3 miles up the road to work and back at 10mph.