It serves as a perfectly fine illustration of ignoring the content of an argument due to preconceived notions derived from the argumentator’s easily identifiable qualifications. I say “easily identifiable” because a persons REAL qualifications are nearly impossible to determine.
To use your illustration, are only paid basketball player’s entitled to give arguments on basketball? That would be ridiculous. Some pro-ball players can’t SPELL argument. In a more practical vein, are pro-ball players the best people to teach basketball? Maybe they are qualified, but maybe they are not. There are many things required to be a teacher. Having experience is insufficient to be a teacher, or give arguments, or even speak coherently on a topic. I have had a few professor’s that had NO RIGHT to be in front of a classroom, despite them being experts in their field.
On the other side, let’s say there is a person who played for 20 years with zero formal “credentials” to prove it. They were never quite good enough to be a pro, or maybe they were just never lucky enough, or maybe they just had no desire. But let’s say they are exceptionally in tune with their own body and how they perform their actions. Lets say they are also exceptional at verbalizing those internal understandings. That person may be the best teacher in the world.
Let’s take this illustration a bit further. Let’s say this person did teach, but never in a formal setting, just on random lots in NYC. Let’s say 20 years later, three pro-ball players came out of the same place in NYC and people wanted to know why. When these three pro-ball players are interviewed they all respond with, “It was all Mister Smith” (where Mister Smith is the hypothetical person I have heretofore created).
What if the public outcry was similar to these boards, “Well who the hell is Mister Smith? He has no right to talk on this subject. I can’t find his LinkedIn profile!”
Should such statements negate what Mister Smith has to say about basketball?
This hypothetical story may or may not be real. It certainly wasn’t intended to be real. This story was designed to illustrate something believable, to show that credentials are not experience, and thus arguments are not credentials.
An argument in the form of data, words, math, logic, whatever either stands or falls on its own. Sometimes an initial argument requires more data, words, etc. to support it, but what it never needs is credentials of the SPEAKER. The speaker only needs to prove his argument, never himself.
If you cannot discount the merits of an argument, you only show weakness when you resort to attacking the speaker, no matter how fancy or vehement you are when you justify that attack.