[mthoms]

Requiring people to update to the latest version as a condition of providing support is perfectly reasonable.

Giving something to me for free and then altering that free thing at a later time against my wishes is not reasonable IMHO.

Consider an e-book: would it be acceptable to give out free e-books, then change that e-book (remotely) at a later time? What if those changes remove value? Or, what if they introduce content that you find highly objectionable?

Now, imagine a future where every (digital) thing is like that.

Docker can do whatever it pleases in accordance with its licensing, but we don't have to like it.