The following item in Power...Settings... states:
Wi-Fi can be turned off to save power
You can see that the option is currently turned on. That should mean that the system is allowed to turn off the Wi-Fi to save power.
However, when I turn off that option, my Wi-Fi is disabled (turned off).
I'm attempting to tell the system that it is not allowed to turn off Wi-Fi to save power.
However, when I turn off the option it actually turns off the Wi-Fi. It's seems that this item is not described properly in the Power....Settings...
Note: This option was the same under Ubuntu 18.04 also.
That's not what it means. Turning that off turns the WI-FI off, not the computer's ability to turn Wi-Fi off. It has the "turning Wi-Fi off can save power" subtitle to tell you why you might want to turn Wi-Fi off. Just leave it on if you want Wi-Fi, or off if you don't.
For those of you actually trying to do what the feature says, e.g. Disable Power-save for Wi-Fi, you have to... use a text editor.
Edit your
/etc/NetworkManager/conf.d/default-wifi-powersave-on.conf
and changewifi.powersave = 3
towifi.powersave = 2
Now that the solution is out of the way, let's dwell on the embarrassment to the English language. Wi-Fi can be turned off = Wi-Fi WILL be turned off to save power. Really? Can = WILL?