A few occasions I have come across over the past year or two have made me realise that most pilots are unwilling to discuss issues with their aircraft, or even the type generally.
I found this heavily so on the Socata owners' group, where I started airing (c. 2002) my views on various avionics issues I had early on - stuff like this which was not getting solved. I learnt years later that a number of the "residents" discussed whether to kick me out of there, at that time. There was a lot of censorship there anyway and c. 2006 a bunch of pilots there formed an "invitation only private club" where things could be discussed freely. I was in there for a year or two but left as there was almost no serious flying discussion there. I believe it is still running. In the end the main group kicked me out in 2008.
In retrospect it seems that there may be a number of reasons why many owners don't want to discuss issues openly:
They want to be able to sell their plane one day (and some of them will have removed the rectification work details from their logbooks - no kidding)
They want to sell their plane now (probably discreetly)
They bought the plane on finance (loan) and don't want its book value to be any more below what is outstanding on the loan than is absolutely necessary 
I think buying piston GA planes on finance is probably a lot more common in the USA
Their plane is still within warranty and washing their laundry openly will terminate their dealer support (I found this myself too)
Their plane is out of warranty but some issues started during the warranty, and that is a much more sensitive scenario for getting them resolved
There is ongoing litigation
The type specific user group they are in moderates (deletes) postings criticising the type
Few people want to admit they spent $XXXk on a dog...
Of course I think that my aircraft is better than any other aircraft (until I buy another one) but I have no problem discussing any technical issues.
How many aircraft owners have an aircraft under warranty? 0.01%?
I can't confirm your observation, most owners I know are very open about the issues they have. The type club I'm in (Cessna Pilots Association) is completely free from anything like you report from the Soccata group. Most posts are about technical problems, this is what makes people join the type club in the first place.
This reminds me of a funny situation I once had. My fancy Siemens induction stove broke within one year after new. Service technician arrived and repaired it. I asked him whether this product often breaks. He answered all the time, he spends his whole day fixing those stoves and hasn't seen a working one in a long time
I haven't seen any censorship on commanders owners group. They discuss every issue.
Likewise on COPA: plenty of open discussion there as well.
Not with the Mooney crowd. Mooneyspace and the Mooney pilots group discuss issues quite openly.
Peter: Their plane is still within warranty and washing their laundry openly will terminate their dealer support
Their plane is out of warranty but some issues started during the warranty, and that is a much more sensitive scenario for getting them resolved
I know several cases first hand belonging to those two categories. Some issues were affecting an entire production year of a specific aircraft and were fixed free of charge (which would have been a significant 6-figure sum requiring about a month of ground time!) by the manufacturer several years after the warranty had ended. But only because everybody remained silent about it. People will only discuss this kind of stuff openly once the manufacturer refuses to rectify the problem at his own expense, but as you say, this may reduce the market value of your aeroplane significantly.
Few people want to admit they spent $XXXk on a dog...
That of course too. Especially if they had been warned beforehand.
But I see that as a general tendency in groups that "worship" exotic and niche market products - which in terms of numbers manufactured every aeroplane will qualify as. I know from experience because I generally prefer exotic stuff like Macintoshes, Cameras from Sigma or calculators with "reverse polish notation" entry. Nothing other than unconditional praise is tolerated on the relevant forums just like in a real religion.
No one sensible can possibly argue that RPN is bad. All calculators should be RPN. It would put an end to those silly Facebook memes trying to trip people up who don't remember the precedence of operators :-)
I've never noticed any caginess about discussing aircraft problems, but then again I've always owned ancient aircraft. The few people I've known who have owned new or nearly new aircraft haven't been afraid to speak out either if they've suffered from a manufacturing defect.
I guess some forums / organisations have political or other allegiences with cartain manufacturers, and moderate their members and their posts to toe a party line. Seems pretty harsh to ban people for expressing sensible opinions or thought provoking arguments.
As a part aircraft owner, I am concious neither to say anything about others in the group, or something about my base that could cause me, our group, or our aircraft any problems. Then again I fly a PA28, so there is nothing new that hasnt been written about for many decades that would be new to a forum posting ;-)
There is always the hope that some of the companies or products we discuss, do take on board their users opinions, through forums, and improve their products or services.
I love it that RPN is so misunderstood and hated. I could always leave my calculator on my desk without fear of it being stolen.
The American Bonanza Society doesn't censor complaints and is not always on the Beechcraft side. The ABS is a great resource for maintenance information and resolving type issues.
