This was, is, a common refrain as Google slowly but surely ensured that Firefox users would run into blocking issues and mysterious performance bugs, every week

This was, is, a common refrain as Google slowly but surely ensured that Firefox users would run into blocking issues and mysterious performance bugs, every week, that disappear with merely a user agent change. Mighty convenient a supermajority of the time, these bugs. At some point when your scale is big enough and you are the dominant incumbent, whether something is due to wreckless accidents or intentional or "blind"/ignorant malice is a moot question. The responsibility is (and so too should the punishments be) the same. That must be treated as the necessary cost of operating at this scale.