That's because you are not setting the options correctly. Don't blame the OS for this one.
Right click Desktop, Personalize, Lock Screen, Screen Saver Settings.
Click on Change power settings on the lower left.
For whichever plan you are using, click on Change plan settings.
Set Turn off display to 0.
Save changes.
That should do it.
I don't have "0". I have "never", but I want my screen switched off after some time.
The issue is that the screen appears be switched off a minute after the screensaver locks it, and not when it's supposed. eg: I have the saver set at 8 mins, but the switchin set at 20 minutes.
Okay, I found what's wrong. The screensaver was reset to off sometime and I didn't notice.
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