It depends on how you define "retrospective." Reading the thread, people with pre-existing accounts that did not use the domain feature found they could not start using it, and others that did use it found they could not change it.
While some people may feel entitled, I think it's more a lesson on what not to do. People will always complain when you make something they are using worse (even if you have a good excuse like abuse). That's not the issue. The issue is that when you are a platform company, people get really nervous when you're not open about changes you're making to the thing they're building their business on. Of course it's their right to change their service. Of course they're allowed to do it silently. But it damages trust.
Personally, I just make a mental note to keep that in mind when running my own business.