"ISP rep" here (from Germany though):
It's a common fallacy that people assume they know more than my colleagues and me. People usually assume that because they know stuff about tech in general and can distinguish a RJ45 from an RJ11. Thing is, that's not the issues you are dealing with. People who tell me that they know better than me anyway tend to ignore that they have never even thought about the inner workings of a landline or mobile network. So your knowledge might not be applicable at all. How many times have I heard from tech savvy people that "this literally can be just some button you don't push because incompetence".

Why would I argue with you for an hour if that were the case, eh? And Even if that were true and the employee has no clue what you're on about, the employee will know what works and what doesn't within their IT. They may not know why, but that doesn't matter in the end, does it? It doesn't matter if that rep knows a Lan port from a serial port, only thing that matters is that they know "doing this will lead to an error"

Besides, people tend to heavily confirmation-bias the shit out of every interaction with us. How many times I had people who "worked in it and thus know a thing or two" and then went on to ask stuff on one IQ level of "earth is flat", then misinterpreted my... Hesistant reaction as incompetence and felt confirmation... A customer asked me once to open a port on our infrastructure for him because he "worked in IT and knew that we can do that" and since he could not have done anything wrong on bus end, the port HAS to be closed on our end"...`