Sure sure.

But if you were handed either a Samsung note or a Windows laptop that belonged to someone else. Where you wanted to quickly sign into your bank account.

What would you feel more comfortable to use?

Arguments of user freedom also includes malware freedom. And for the average user who just wants to consume, that's a decent tradeoff.

That's why there's tamper-evidence - my phone displays a message stating it's rooted on boot.

Getting the best of both security and user-freedom has already been done, but manufacturers prefer to lie that the choice is exclusive - that we can have security or freedom, but not both. And as the article clearly shows, they delivered neither.

I really wish we'd optimize for me owning my device rather than me entering my bank details on someone else's device.

One of these use cases is a lot more important than the other.