Personally, I expect what I paid for from a free service, and I consider depending on gifts and uncertain platforms a reckless risk.

But, as a business whose prosperity depends on the goodwill of masses of users, Docker can and should "defend their revenue" in a way that minimizes collateral damage in the form of

1) gratuitous bullshit, untrustworthiness, lack of transparency, and perceived evil intentions (e.g. their second announcement)

2) technical uncertainty and security risks (for orphaned images of uncertain status)

3) inconvenience, without additional revenue, to the vast majority of users that aren't included in this the shakedown

There are rational businesses and there are businesses that drive them away their customers; in the long term, the former tend to "defend their revenue" much better.