That argument doesn't seem to make a lot of sense to me. If the goal of software is to address the ever-evolving needs of customers and to correct deficiencies, open-source provides just that momentum. In my experience those "dev egos" go where there is
a high value proposition.
Open-source is self-correcting; features that have no inherent value get atrophied away (or remain unused) whereas substantive ones become magnets for developer energies.
Developers / Customers adding value to products that they use and enjoy using.... What a concept! And far from companies losing control of product development, I think there is plenty of money to be gained in support services and packaging the best-of-breed
concepts from open-source development into commercial products that non-tinkerers can use just as they do today.