Soapy picture on a monitor with a macbook. What to do?

Question

macOS

I bought a macbook pro, connected it to a dell u2419h monitor, and was surprised that the picture was somehow blurry. Not as clear as on the MacBook screen. Moreover, if the monitor is connected to a laptop with window 10, everything looks clear. What could be the problem? Why does Windows with a rarefaction of 1920 look normal, and a macbook connected to a 24-inch monitor lathers, despite the fact that it (on a macbook) has a resolution of 2600. It seems that the mac os system is not adapted to display correctly at resolutions below 2600px, This monitor does not support resolutions higher than 1920.

Answer 1

because there is hidpi on the macbook screen, but not on the monitor screen (and will not be until you change it to 4k and higher).

Answer 2

add it as a separate screen, not as a duplicate of the main screen