Was Prufrock a typical man of his times or was he unusual?
Concerning "The Love Song of J. Alfred Prufrock," remember that Prufrock is a literary character. He's not any kind of man. He's a narrator of and character in a poem. Thus, your question can't really be directly answered.
As a literary character, however, he is representative, or at least is seen by many as representative, of modern man. Prufrock questions himself, lacks self-confidence, and is anti-social. He's not even sure if he wants to meet and start a relationship with the woman he is supposed to go to meet, because doing so would result in tedious, ponderous, repetitive social activities.
He appears to be somewhat inept at social intercourse, and is well aware of his aging and mortality. This poem is heavy with despair and angst.
In short, gone is naive Romanticism and the Victorian predicament (the question of God's existence)--the issues inherent in those have been decided. Prufrock may well represent modern man, or at least educated, fairly well-off, white European and American males: those that dominated literature and philosophy in the Western hemisphere for much of the 20th century.