I just don’t find laptop monitors very ergonomic. I use a 27” 4K screen and put it so far away that 200% scaling is ideal, then have the desktop disable the laptop monitor when it’s plugged in. If I’d have the office space I’d use a 65” TV as a monitor and put it many meters away, that’s just my preference.
I can upgrade your claim: laptop monitors are not ergonomic, period.
Laptops force you to place your hands close to your monitor, which is really bad ergonomics - either you place the laptop low and kill your neck (looking down for long periods of time can cause spinal fusion and back problems in your 30's - careful with how you hold your cell phone:), or you place your laptop at head height and kill your wrists.
If you value your body at all, you'll keep your keyboard and display in their appropriate places and well separate from each other. Laptops should only be used in case of emergency, or while docked.