The point isn’t what you call it. OP’s point was and I agree that you don’t need to have full control over every device that can possibly run code. Just let it be a device that does its thing.

It’s the difference in people that want calm technology vs “power users”. I want the device to exist waiting on my input and even though I have deep knowledge of its internal systems and processes, I don’t care, I just want it to work, solve a problem for me, and I’ll put it away.

Go ahead and root your phone to do whatever actively complex thing you need... it’s a tool for me and I personally want the walled garden to prevent it from possibly not working when I need it.

I argue that if the device sends data to third parties over radio/internet and/or the manufacturer can remotely push updates that changes the devices behavior then users must have full control.

Something like that should become law.

Then manufacturers can keep devices locked down as long as they stay out of the surveillance game.

That's not how I read the op, who said "It's a phone, use it to call text and guide and browse some internet. That's it". The tone in that reads not like "you don't need to..." it reads like "you should not...", which I disagree with. I rarely use my phone to make calls. I use it as a multi-function tool of tremendous capability. If I wanted a simple flip phone, I would have bought one of those, instead.