Before I go further, let me point out that I am well aware such attitudes are prevalent throughout the Internet nowadays. It is the world into which we have grown. So, I realize these attitudes are not restricted only to writers.
But with writers, these attitudes are beyond foolish. The majority of things argued over generally have very little to do with any kind of reality when it comes to readers.
Remember readers? They are the ones for whom we write. Even if we initially write for ourselves, to have any success we depend upon readers.
Readers don't care where you sell your stories or the nuts and bolts of how you write them. Readers mostly don't consciously care whether a story is in first person or third person. They don't care if you use an Oxford comma or not. They don't care about the stuff that goes on behind the scenes.
Readers want to be entertained and/or informed. That's it. It's quite simple.
I can remember my days as a newspaper editor. There were occasionally silly arguments among editors over the slightest details. Should this line be a one point line or a half point line? Should this headline be 48 points or 52 points? While there were obviously aesthetic purposes behind such argument, the reader doesn't care. Not only does the reader not care, the reader doesn't want to care.
To repeat, the reader simply wants to be entertained and/or informed. Only other writers will look at one's work and study it for particularities. Okay, maybe some teachers will look, too, but for the majority it will be only writers and those interested in the craft of writing.
I am not suggesting writers should not know their craft, nor that they should not know what they're doing. All of that will come with experience and possibly some training, formally or otherwise. No, writers do not need to look like fools on the written or digital page, at least not if they hope for some success. But writers need to recognize that many of the things they argue about are not really worth arguing about.
You tell your stories your way. I'll tell mine my way. You reach your readers in a manner you deem fit and I will do the same on my end.
The truth is, whatever works works, when it comes to writing. Some writers have built careers going against the grain, breaking the rules. Why? Not because they were necessarily some genius, but because they figured out a way to draw in readers with their words. Again, whatever works works. Anything else is just opinion, not fact, and not worth getting hot under the collar.