> ES and other companies have a business that sells a managed version of their product.

Therein lies the flaw in the argument. If a company decides to develop something and open source it, it's not a product. If the company chooses to assign their time and resources to help develop it, great, but the moment it no longer becomes beneficial for them to keep supporting it, they'll drop it and leave it to the community.

Many companies invest time and resources into furthering open source projects without being the owner/creator of it. This is no different, whether they created it in the first place or not - they chose to open source it.

Building your business around something that you give away for free will always be a terrible business model.