My Brethren
Problem is with the graphics driver from Intel. If you have Intel Arc video card and you updated the driver recently, the software bug in Intel Arc graphics update driver has caused this issue. If you have two screens you will notice that cursor disappears on 2nd screen completely, and within 10 sec the cursor disappears on primary screen.
The fix is to download the updated driver from October and it will fix the issue.
As a former software developer when the cursor disappears within 10 sec tells me some employee at Intel has messed with the driver and made life miserable for most users. Intel will deny it. MSFT didn't do their due diligence and incorporated the driver in their recent update.