That’s true, but also skewed by viewing history through moral failings on a large and public scale. One could easily point to Islam and extremist views or Buddhists and their persecution of Christians and ask the question, “What good have they really done? Seems like most don’t live their faith.” We tend to look at only at the large and public failings of others and never the good that happens instead. Throughout Christianity’s history, there have been amazing things that have happened throughout the world by people who were so influenced by their faith they lived out these core principles and made massive changes for the better of humanity. For example: William Wilberforce who led the charge against the slave trade. Harriet Tubman who ran the underground railroad. Dietrich Bonhoeffer who opposed Hitler during WWII and was eventually murdered in a concentration camp for his part in Operation Valkyrie. William Booth who founded the Salvation Army and worked his life among the poor. Elizabeth Fry who caused massive prison reform. Blaise Pascal who helped advance mathematics, physics, and was a brilliant inventor and defended the scientific method.
It’s easy to see things through grey colored glasses when everything looks grey and corrupted, but there are those of us who live more in obscurity trying to advance God’s Kingdom through grace and humility. They’re less apt to be remembered, but perhaps that’s the point of Christ’s teaching about becoming less.