I think you have brought up an interesting development. I have watched this trend of more open systems with great interest. I saw how well the Apple II sold when it was an open system and how interest in the Mac dwindled away when it became a closed system.
We see the same struggle in many areas today with tablets, smart phones, and an ever increasing number of interesting products.
From my observations, you have two types of people. One type buys a tool for use against a single problem. Most users fall into this category. Then there are the more creative individuals who see the device not as an end product, but as the beginnings of something different. This is the group that I see who will exploit an Open system and take it into new applications and product improvements.
There in lies the dilema for the producer. Do you want to just sell your tools for the use intended, or do you want to use your product as a vehicle to inspire the next generation of next tools?
In my experience, the number of interesting devices that were developed out of the open IBM/Intel powered PC has left an entire world with useful desktop and portable computing that has completely changed how business is done. Whereas the closed system is still only used in niche markets where the tool supports a base of happy users.
So which way is better? The last twenty years says open source and easy access wins over closed systems by a factor of about 300 to 1. So if I am building a new tool and want to be in business for the long run, I would go open source. The return on investment has clearly been on that side.
Are the conditions the same today? I think so. You have many more people today who want to implement their ideas and with the internet, you can show case your talents much more quickly than at any time in history.
In an era where you need to demonstrate that your personnal capabilities are better than other applicants, the new media dominated open sources can give you a place to Prove you are better. In a competitive world, that is a distinct advantage.
So to shorten a very long story, I vote for open source. You have more to gain then you have to lose. Plus history has shown, the more you try to control an idea/product, the faster it escapes.