WD is not worthless. First, it does indeed displace moisture. This is not so much of an issue with chrome bores, but after exposure to soaking rain - when I'm not able to clean right away - spraying the bore and wipe down of outside metal will keep things from rusting over the short term. Repeat: short term. Go to Brownell's and do a search.
Lousy lube? Yes, definitely.
Gunks up? Not. Do the following experiment: spray a teaspoonful into......say.......a teaspoon. Let it sit.......like forever.........when it congeals report back to me. Best not hold your breath. Does home heating oil congeal? Why does this myth persist? B/C WD's solvent vehicle penetrates and is free to sometimes interact with other lubes and greases.........displacing (duh!!) them to places they don't belong..........resulting in problems when the solvent is gone.
Cleaner? Damned right it is. Actually, it cleans at least as well as the wonder-fluid CLP. No, make that cleans powder fouling better than CLP. It does better with wad plastic (shotguns) than CLP. Not as good a lube as CLP, not as good a preservative as CLP (Brownell's folks disagree here), but a better cleaner.
Let's be clear: CLP is a better overall product for ARs.........no argument here.
Generic condemnation of any petroleum product is unwarranted. Even 3 in 1 oil has it's uses. You need to go to the effort of learning about the product in question so that you understand it's capabilities. WD is no "worse" than lithium grease or sewing machine oil. You have to understand the properties to avoid the pitfalls.
Rant off.
Sam