I think the parent commenter is just saying that it's not something you can actually believe, just like a company saying they'll never sell your data.
Sure, that's the intention but when someone comes around waving a checkbook, they can in turn buy you and shut you down, sell your customers' info, etc. Sure, its not YOU allowing that to happen but by ceding control you essentially allowed that to happen.
Clearly, you need to always be prepared for your partner to go away, but you still have to work with other companies.