From my perspective . . . a forum member who provides information/insight based on experience & knowledge when it comes to customizing, kit bashing, etc. about figures, vehicles, etc. could be called an expert or an experienced member in the same vein as those who have served or currently serving in the armed forces providing feedback & knowledge on 1:1 military stuff.
With that said . . . many of us posts our opinions & views and we all the know the saying about opinions.
When we tend to discuss matters related to say . . . business matters in terms of how & why a company should do this & that when it comes to a product in terms of design, marketing, pricing, release, etc. I take it as one's opinion & perspective, but from time to time there are posts/replies where it comes off as if the post/reply is apparently "I'm the expert in this and I know what I'm talking about."
The context & intention of this thread is not come off as to why we're an "expert" in a negative tone, but to discuss so why some of us rationalize that we're an expert on a particular aspect of the 1:6 hobby, but especially when some of us start posting/touting business related matters of the hobby as well.
Personally speaking, I don't claim to be an expert or a know it all member about whatever. I do know a fair amount of 21STCT and 1:6 female figures along with odds & ends within the 1:6 hobby. That's it for me.