A great way to respond to this question is just say ”what do you mean by that?”
they will likely respond with a general claim that they copy the big brands, so you answer ”oh really, I didnt know that, which ones are these copies of”
The truth is most manufacturers are copying someone elses design. Take most Scotty Cameron putters for example. To use your freinds own arguments, The Scotty’s are blatant copies of Ping Anser, right! (would be even more funny if thats the putter they have)
Your friends are simply conflating forgeries with component clubs. They dont know what they are saying, hence asking what they mean by that, will cause them to stumble over their own words.
I have lost count how many times someone has admired my Maltby DBM irons, and asked what they are. some have assumed they are Miura or as one person said, a ’boutique japanese forging’. Not one person has ever said anything but ’looks awesome’.