It's possible for competitors to build replacements for iMessage, too. In fact, in many parts of the world, those competing apps are more popular than iMessage. You can go to the app store right now and install these competing apps, usually for free.
Other messaging services are available on iOS. In much if the world, iMessage is barely used. This is not lock-in, at all.
If anything, this is lock-out - it's a service that Apple provides to its customers and they don't want 3rd party clients and/or non-customers using the service.
Exactly. Evading disaster doesn't make someone like this reconsider their decision making process and act smarter next time, it shows them that they're a goddamn genius who can do no wrong.
According to that link, all the browsers do implement the non-experimental parts of that API. The other features seem to be ones that Chrome has shipped unilaterally - the links to the standards docs seem to only have Google authors for those bits.
The issue here is a requirement to provide product labels for broadband services, with the intent of letting consumers compare between providers, i.e., before the point where they inquire about service. I totally agree that they should be required to provide a complete (and accurate!) list of taxes and fees to a potential customer before any agreement.
The taxes/fees on telecom services are complicated in the US because we have multiple overlapping taxation authorities who might impose them. Unless you know a person's address, you don't actually know what they're on the hook for.