Yeah it's very unlikely that companies are going to start to want to share their source (which they paid good money for) with competitors for free. I don't think there's anything pointing to this being a trend, and anyone who believes in it is probably just mistaking the expanding software world in general for an increase in open-source (remember, even the population of earth has gone up 20% since 2000).
That's probably true - there can be good reasons for companies to share their own source code with the customers of their competitors, though.
Only if the support question is adequately handled. "You have the source." is off-putting to the large majority of people trying to solve a problem.