That's a very malicious way to put it, and you could easily google how to "deregister" your previous apple phone's number.

Also, your family has total control on how to send it, they should just long-press the send button and choose to send as SMS.

It's not malicious. It's the reality. I already have deregistered my phone number. Their contacts for me have no mention of my email address now. They are sending a message to a phone number, and it still sends it as an iMessage.

You aren't being humble and understanding how terrible and complex the situation is. And it is not our faults. It is Apple's.

And by the way, that de-registration process only exists because Apple was sued for this before.