Probably, on other forums, going FF doesn't mean selling all your gear and completely changing brands. It's a much more intensive process for the members of this forum. It's tough to watch some one make that decision based on expectations that aren't realistic. On the other hand, while I expect the Pentax FF to blow other FFs out of the water, for some images, just based on their pixel shift technology, there will never be a D750 type camera. But, buying a certain camera based on bad information about the values of certain features? I think that will always be here. At least I'd hope so. The comparisons here tend to be looked at feature by feature, for the photographers, and FF vs APS-c for many of those who post.The simple fact is, it was never an FF vs APS-c argument. It was a this feature vs that feature.
For example on a D750 vs K-3, you have faster AF on a D750, and slightly higher resolution (less than 10%) but a higher frame rate and bigger buffer on a K-3. It's not per se an APS_c vs FF trade off. When you get into a 6D, the trade off is that whatever sensor is used in the 6D though not as good low ISO performance, has very good high ISO performance. It's not an APS-c vs. FF argument, it's different features on different cameras argument. The longest discussions are with people who honestly believe, that there is a better camera or format, that is better for everything. Anyone who comes in eyes wide open gets very little discussion.
And the hardest people to convince are those who think because one FF camera does this or that, they all do. They look at images for a D3x, and assume all those features are available on the D610 they just bought. That's when the whole APS-c vs FF argument gets ridiculous. This FF camera has this and this APS-c camera doesn't have this, so every FF camera is better than every APS-c camera. There's a lot of educating to do. And most of it won't disappear because Pentax has an FF. What will disappear is people leaving the brand because they want to try out an FF, and see what it's like.
And it will be really good to hear the end of the "I want to use my 30 year old lenses used as they were designed to be used" type complaint. The excuse for that type of whining will be history, although if the Pentax FF really is $2500 people will be clamouring for a cheaper version.
I have 18mm to 400mm covered for a Pentax FF without buying a thing. That is a lot less hassle than buying into a whole new system. SO of course there won't be as many times when it might be inappropriate to buy a whole new system. It will be a $2500 dollar gamble, not a $6,000 dollar gamble.
The type of post I look forward to seeing the end of will be the " My Canikon FF is so much better than anything Pentax has to offer because it's FF", type of post. The ignorance displayed in some of those posts is off the charts. We've had more than a few newbies on here proclaiming themselves god's gift to photography because the bought a 6D, D610 or D800/810. That's what I look forward to seeing an end of.
I wonder if you get those on those other forums.