I do not want to adjust the contrast of my 16x2 LCD display.
OK no one is forcing you to.
However do you want to see the display?
Then you will have to put in a pot, adjust it until it looks right. Remove the pot and measure the resistance from the wiper to each end. Then get the closest value to the measured ones and replace the pot with these.
Then hope that you don't need to adjust it again due to aging of the LCD or temperature changes.