I've worked on some MIM strats and found the necks to be pretty damn good, they need minimal fretwork and are pretty straight. Can't say the same for Gibsons, in fact the build quality of their Chinese made Epuphones is often superior iME.
But more generally, a decent guitar will allow a bad guitarists to make more imporvment than if they were using one that was hard to play. So yes, there is an argument for buying a good guitar even if you're a bad player because it'll help you make quicker progress. And you don't have to spend a lot of money these days to get a decent guitar, so long as it has been set up properly with levelled frets. PRS SE and CE series are excellent, I've been fighting GAS for the Hollowbody II SE. Used Ibanezes are also often bargains, from the Artcore series (I have an AWD which plays like butter and has a killer stock bridge pickup) to the S-series (of wich I also have one which has been modified into a Chrome boy tribute). Gidin are also fabulous value second hand. If you shop for these models of guitar that were mid price new but second hand, you'll get great value.