Due to the technology used on IPS panels, some monitors have inconsistent brightness when observed from different angles and distances. This appears like a glow that’s somewhat visible when the screen is either all black or showing dark content. As IPS glow is technology-related, it cannot be completely prevented or eliminated. Thus, it has been widely accepted as a unique feature of IPS panels. This phenomenon is exclusive to IPS monitors and is far more common than TN/VA light bleed, although not as severe when it does happen.
There are some setup tips that you can try to make the IPS glow less visible: