Grayscale not working

It looks like some level of grayscale is being applied since the letters and border are darker than the center sections. It may just not be creating as much of a variation as you’re expecting.
I suspect if you burn the entire image it will be more apparent.
However, let’s confirm that your settings are not posing a potential problem. Can you provide the following:
1. screenshot of Edit->Device Settings
2. run these commands in Console and return output:
$I
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