In other words, if you can't reboot your device naturally, just take out the battery. It will reset. This too, shall pass.
But now, we are to understand that there is a lack of a removable battery on the iPhone.
Every relevant gizmo I've owned, regardless of the brand, has always provided a way to take the battery out, and either put it back in or replace it effortlessly if that's what needed.
Apple engineers surely have their reasons for this, but I can't say no removable battery helps me in the comfort level dept.