Color bit depth of built-in display is 6-bit instead of 8-bit

[evoalg]

HP Elitebook 650 15.6 inch g10 Notebook PC shows a color bit depth of only 6-bit in the built-in display instead of 8-bit.

When I go to:

Settings > System > Display > Advanced Display it says "Bit depth 6-bit"

When I keep drilling down to: Display adapter properties, it's an Adapter Type of: Intel(R) Iris(R) Xe Graphics

I'm wondering if this is a hardware limitation of the monitor or if it can be configured somewhere to 8-bit? I searched but I couldn't see any specifications saying the built-in display is only 6-bit.

[evoalg]

I should say that when I plug in a 4k monitor via usb-c to usb-c as an extended monitor, the 4k monitor displays the colors fine, and windows says the 2nd monitor is 8-bit. At the same time, the red's look washed out on my built-in monitor.