widdly, your opinion is just wrong.
Harmonically, some rock music pushes the boundaries - especially rock fusion (which is a form of rock).
Some of the progressions are out there, especially with Al Di Meola and the such. In that music, you will find bitonality, and distant ii -V - I progressions, littered with tritone substitutions and temporary modulations. Such things are at the cutting edge of contemporary harmony.
And if you are talking about Pantera as rock, then you must also place bands such as Lamb Of God in this category.
And Mark Morton is certainly not a lazy, or unmusical guitarist. Technically he is phenomenal, and his timing is impeccable. Try playing demisemiquavers at 120bpm as accurately as Mark can.
I've performed in masterclasses to classical players such as John Williams and Julian Bream, and it may surprise you that those who are at the top of their game don't insult any musical style - all music is just as valid as the next form of music. John Williams listens to rock as much as he plays classical. I know this for a fact.
Plus, you are adopting a super-philosophy. If your way of thinking was carried through, there would only be one musician playing the most musical, most technical music on the planet. You are adopting a super-philosophy.
The beauty is the variety within music, as much as the actual music itself.
To be at the cutting edge of any style requires effort. The best rock guitarist will practise just as much as the best classical guitarist.
I know you are trying to seem educated, but your opinion smacks of ignorance, due to your dismissal of a large chunk of music. I think you should open your mind a little.
You are showing by your comments that you aren't even aware of a large chunk of rock music e.g. players such as Al Di Meola and John McGlauchlin, or even players such as Allan Holdsworth, who some would class as a rock player. If you were aware of these players, you wouldn't insult rock music. Your opinion is therefore ill-informed, and lacking in insight.
I also think if you are dismissing the people you are dismissing, you should post an example of what is a harmonically gratifying and musical guitar solo. Let's hear it.
And remember the words of Sibelius - 'no statue was ever erected for a critic'.
RE the subject at hand - I don't like to think of guitarists in negative terms i.e. 'overrated'. Guitarists just do their thing, and it is unfortunate if some people label them. I think every guitarist has something to offer. We can learn from them all. Even the technically 'basic' players - they show us that music doesn't have to be technical in order to be musical.
It all sounds nearly impossible to the non-musician anyway.