This is exactly it. I'm amazed that so few people in this thread are recognising this key ambiguity which underpins the confusion. As Wittgenstein writes in the Tractatus[0]:
> 3.323 In the language of everyday life it very often happens that the same word signifies in two different ways — and therefore belongs to two different symbols — or that two words, which signify in different ways, are apparently applied in the same way in the proposition. Thus the word "is" appears as the copula, as the sign of equality, and as the expression of existence; "to exist" as an intransitive verb like "to go"; "identical" as an adjective; we speak of something but also of the fact of something happening. (In the proposition "Green is green" — where the first word is a proper name and the last an adjective — these words have not merely different meanings but they are different symbols.)
> 4.003 [...] Most questions and propositions of the philosophers result from the fact that we do not understand the logic of our language. (They are of the same kind as the question whether the Good is more or less identical than the Beautiful.)
[0] Hilariously republished here by Buzzfeed as '7 Fantastic Ways To Distinguish Between Sense And Nonsense': https://www.buzzfeed.com/ludwigwittgenstein/fantastic-ways-t... It's such a mindblowingly profound work of philosophy, especially the kinds of philosophy that programmers are often unknowingly engaged in, that I feel you just can't read it all at once. You have to keep referring back to tiny chunks of it, as you start to understand their meaning and significance through epiphanies arising from particular concrete problems you wrestle with in your life.
I can't help but think of Linux when you say this, and Linux is strictly centrally controlled
Most of the benefits of open source (for the company) would come from running it as a community project, which would imply giving up some of the control. Simply throwing the code over the wall without accepting contributions doesn't meaningfully benefit the company. There are of course graduations between "don't accept any contributions" and "let the community run it", but that's just different levels of giving up control.
I think "11. It takes steady income to sustain long-term R&D" is still the key aspect. Without money, software doesn't get maintained to a high level. Some projects work because many companies depend on it and contribute (but they wouldn't do it - or at least not nearly as much - if the project was strictly centrally controlled), but many other projects are basically one company running and publishing it and many others using it for free.