Usually with a desktop computer, if I run sudo shutdown -P now, the computer switches off completely and I can switch it back on again with a button. (Likewise, if the computer crashes, I can force a restart by holding down the power button for 5 seconds or so.)

The raspberry pi doesn't have a power button. In fact, if I run sudo shutdown -P now, the power led still seems to be on, and in order to start it up again, I seem to need to unplug it and plug it back in again. (This seems somewhat analogous to "It is now safe to switch off your computer" in old versions of Windows).

At what point is it safe to pull the plug on the raspberry pi ? Am I doing something wrong ?