Okay, I have no problem with that notion in general. It's true in a very basic sense. The problem is with how that idea is being used to exclude me or gatekeep me or etc from the conversation. I must essentially 'play more games' or my opinions get to be immediately dismissed. That's never going to be a position that yields a productive conversation between anyone that holds it and me (and most likely anyone else in a similar position as me).
I'm trying to think of a productive, non-confrontational way to address this concern.
It's not that ideas of trad play are dismissed or denigrated out of hand. There is nothing wrong with them! As many folks such as Campbell and others have stated, we're playing trad style games right now --- many actually playing 5e!
I'm personally running an Edge of the Empire campaign right now that's predominantly "trad" in approach. All of the things about world building, encounter design, map and key searching/hunting/discovering are all part and parcel of the way I'm running this game.
Before I started the campaign, I actually posted here asking for advice on how to do effective, principled, trad map and key play.
Is it different than 5e? Of course. Purposefully different, due to the narrative dice mechanics of nothing else. But as a GM it's not a 180 degree pivot from when I ran Pathfinder or Savage Worlds. It might be a 15 degree vector shift.
Ironsworn, on the other hand? That's a completely different GM sensibility on just about every level. Applying my long-ago-assimilated "trad GM DNA" to my Ironsworn play would be a disaster.
If D&D 5e is driving a Tesla sedan on a flat interstate highway, then FFG Star Wars is driving an SUV on a flat interstate while pulling a trailer with a tied down 4 wheeler. A little different, sure, but mostly just a few different constraints.
Ironsworn, on the other hand, is driving a semi truck down a looping 2 lane mountain road at a 6% grade.
At their core all three meet the general description of "piloting a motor vehicle", but one of the three is a significantly different experience.
If you're the driver of the sedan, your observations are welcomed on any of the three (or more) driving modes. But sometimes the truck driver is perfectly at rights to say (assuming you've never driven a big rig), "I appreciate your input as being well intended and genuine, but the thought behind it just doesn't match the experience."
And sometimes, unfortunately, it may mean there isn't a productive discussion to be had.
Why is there a need to set yourself up as an expert? What do you hope to gain by having expert authority in the conversation?
Clarity, mostly. I want others who have similar play experiences to provide feedback and input. I don't want to be misunderstood when I talk about particular experiences that will be unfamiliar to those who lack the same experience.