People stubbornly believe that you need a mirror for good image quality. This is reflected in the sales numbers of DSLR versus mirrorless systems. Why?
Because people like big things. Remember the SUV ad with Crocodile Dundee Paul Hogan? Or the candid camera trick from Samsung? Or the spoofs from Sony? If two things are equal in quality, people still buy the bigger stuff and then leave them home and take pictures with their phones. This begs the answer to the pain of the mirrorless camera makers. Make a big mirrorless. This is how to do it:
1, Open the CAD design of your current mirrorless.
2, Select all.
3, Click the lower right corner, hold shift and pull down.
Hooray, you have a huge mirrorless camera with 60 megapixel resolution and enough space for 16 function buttons. And a big viewfinder, which is redundant since you have a retina display on the back. The tech bloggers can start salivating. The pixel-peeping test sites can freshen up their colourful little toy shelves and resolution charts. The camera will be a winner. Hasselblad and Leica are already following this logic, albeit at the wrong end of the price curve. There is no need to make this thing expensive: the price of the extra plastic is not much and people are willing to pay a hundred bucks more (but not thousands) for a bigger sensor. Do not even bother with the lens lineup, there are plenty of them already on the market.
And a few years later, smart camera makers can reinvent the wheel and sell the miniaturised, human-pocket sized versions of the monster cameras they were selling. These will be the replicas of current mirrorless systems.