The fact that someone went out of their way to forever commemorate his shitty copper tells me he'd probably be fucking pissed but hey, maybe he was a swindler and a clown.
Today we think of plated items as being cheap. I believe that would be basically space age technology in ancient Babylon. I don't think they had any electrical or chemical way of plating anything. Not only that, I bet you would need to use very pure copper to plate something.
You're absolutely right, if it was actually plating. However, given the contract was for copper ingots, I'd guess the poor quality copper was copper cast into an ingot shape around something worthless rather than what we would consider plating. It could also have been much more about impurities and ores left over from an incomplete smelting/refining process such that trying to hammer or cast the copper resulted in lots of worthless slag.
I've never met the man, and have done little to no business with him, but in my experience if you do a lot of work some people are going to complain about it, and only the pissiest of them would go out of their way to inscribe a tablet about it. Nobody is putting that effort into "went fine, no complaints."
Ea-nāṣir's reputation may be the earliest victim of survivorship bias.
Are we sure we're doing Ea-Nasir justice? Perhaps he was a perfectly fine copper salesman but had a weird and totally unhinged customer review (or complaint) he found funny displayed in his home.
Looks like there were more complaint letters in what is assumed to be his dwelling from dudes either not getting their copper or calling it substandard
I'd posit: He was a fantastic copper dealer, people far and wide purchased his work and instead of going to a better vendor, the user took time to CUNEIFORM a fucking TABLET in response to a merchandise issue.
To me, it's like assuming ford was an unsuccessful company because someone found a pinto review a few thousand years from now.