This question, in my opinion is different from Why is the Haber process carried out at such high temperatures?
Referring to the above link, I understand that why high temperature of 700 K is chosen, i.e, to overcome the activation energy barrier as well as kinetic considerations. However, why is the pressure 200 atm only. Why not 300?
According to Le Chatelier's principle, there larger the pressure, more ammonia will be formed.