Practicality

There's much ado about guns which can fire rather large amounts of ammunition without cleaning or maintenance.

I am not saying that it's a bad thing for a gun to be able to do so.

What I will say is that in most practical circumstances, it's irrelevant.

I've mentioned it before, how much ammo are you going to be carrying?  What's in the gun and one or two reloads is common for CCW.

The standard infantry load when I was in the Army was a mere 210 rounds for their M16.  In Vietnam it was 180 rounds.  That's a pretty low bar.  In actual combat, grunts will supplement their supply with extra mag pouches or bandoliers; but even so 500 rounds is really stretching.

A combat rifle that can shoot 1,000 rounds without cleaning is a nice feature, but that's 2-5 times more than the ammo supply will be.  You'll have a "out of ammo" stoppage before you're likely to have a "got too dirty" problem.  This is why the Army is pretty damn sanguine about the dust test.  The M4 does, indeed, reliably operate until the soldier would be out of ammo.

Luckily, most firefights are over by then too and there's time for resupply and cleaning.

I've had friends who were WW2 and Korean vets.  They've described the abuse the Garand was able to take and keep functioning but all agreed that you could kill it from neglect.

Being a gearhead, I question the wisdom of running your guns dirty and dry.  OK, you CAN; have you considered if you SHOULD?

Is the lack of lubrication and accumulation of dirt accelerating wear?  I think that keeping it clean and lubricated is ensuring longevity.

Cleaning should also not beat the shit out of your gun!  If you are scrubbing so hard that you're leaving marks, you should consider getting treatment for your OCD!  Modern solvents are wondrous!  Heck, even good old fashioned Hoppes #9 is superior for cleaning than anything I was ever issued.

Also, on the solvents topic...  Products like Break-Free were developed to solve a logistics question.  "How do we reduce the supply tail by a couple of products."  That makes CLP an OK, solvent an OK lubricant and an OK protectant.  It doesn't make it the best of any of those categories.  It's so you can stock and distribute ONE item to troops in the field and not worry that they are missing one of three things.  WW2 era bore cleaner is still a better solvent and LSA is still a better lubricant.  And Hoppes beats bore cleaner...