- Hammett is using wah-wah pedal too much during playing, unlike Murray. People often criticize him for that.
Is using -- as in now, in 2019? I have no idea if that is or isn't true.
I do recall thinking sometime after the Black Album came out that Hammett was using the wah pedal a bit much. Regardless, that's a stylistic quibble that has nothing at all to do with the several months old debate that you quoted about whether the members of Metallica are/were "technically inferior musicians than the guys in Maiden."
Nicko is better than average for sure (and much better than Lars), but I think Clive Burr was a superior Maiden drummer than him. Clive doesn't get enough recognition as a drummer.
I stand by what I wrote previously about the technical skill of the three guys mentioned. As far as Burr not getting "enough recognition," I'd say he gets about what he deserves. He quit or was fired (don't remember which), so there's none of the death mystique that attaches to Cliff Burton and Randy Rhoads. Also, and while I'm not saying anything negative about him, I can't think of a single thing he did in his 115 minutes of recorded output with Maiden (plus a handful of B-sides) that I would regard as truly exceptional.