Your first paragraph is not relevant to the phone but the service. That's the whole point I'm trying to make. It's called wi-fi calling and is a service feature not a phone feature. Apple makes it easier but I can still message anyone without a phone just fine.
The problem comes when it costs you money to send an SMS or make a voice call to the person with iMessage but data has no extra monetary cost, for example when you're in a different country.
It's entirely relevant if the people you want to contact don't have any other chat apps. The whole point is the inability to get others to do something slight less easy.
Your first paragraph is not relevant to the phone but the service. That's the whole point I'm trying to make. It's called wi-fi calling and is a service feature not a phone feature. Apple makes it easier but I can still message anyone without a phone just fine.
The problem comes when it costs you money to send an SMS or make a voice call to the person with iMessage but data has no extra monetary cost, for example when you're in a different country.
It's entirely relevant if the people you want to contact don't have any other chat apps. The whole point is the inability to get others to do something slight less easy.