Photoshop CC v 22.0.1 brush tool issue on Windows 10

[#1]

I open a new document (1920 x 1080 pixels) and select the brush tool making it 300 pixels wide. But the cursor does not change and it draws only a single pixel line in the document (of the proper color/opacity).

Screenshot attached.

I'm finding Adobe Creative Cloud to be the biggest impediment to getting work done that I have encountered in a loooooong while. This is a very new computer purchased with one of the graphics cards specifically recommended for the Adobe CC applications.

[#2]

I open a new document (1920 x 1080 pixels) and select the brush tool making it 300 pixels wide. But the cursor does not change and it draws only a single pixel line in the document (of the proper color/opacity).

Screenshot attached.

I'm finding Adobe Creative Cloud to be the biggest impediment to getting work done that I have encountered in a loooooong while. This is a very new computer purchased with one of the graphics cards specifically recommended for the Adobe CC applications.

[#3]

Also, I do not have the caps lock key engaged.

[#4]

Interestingly it is my NEW document that exhibits this problem. If I open another file (like a PNG) the paint cursor is the right size (300px) and acting as expected. If I then select the tab to go back to my NEW document, the single pixel crosshair shows again.