People result to attacking the opposition rather than the argument when they're losing an argument.
When someone attacks the person making an argument instead of addressing the argument itself, this is called an "ad hominem" fallacy.
Just because someone has or hasn't done something doesn't disqualify their arguments. It's entirely possible that someone has researched a considerable amount on a subject and is very knowledgeable. I actually do think 273 falls in this category.
Are there things people learn through experience, which then gives extra qualification? Of course! But it's not the be all end all. Plenty of experienced guys out there spout BS all the time. Plenty of experienced guys out there who think they're some kinda walking god and can say no wrong.
I know which I'd rather listen to.
Plenty of really experienced guys who were extremely proud of their 12s car in the 80s. A lot has changed since then and I'd argue it's in part because you can learn so much more, before the first dollar is spent experimenting and wasting time.