The most major mountain ranges in the world have proven themselves to be distinctive. This distinctiveness is made possible only by a recent history of being sculpted and resculpted by ice.
Now, in this alternate scenario, the history of mountainbuilding remains unaltered, but ice never formed in Antarctica as was the case late in the Eocene back home. No ice, no global cooling. No ice, no glacial erosion. No glacial erosion, no mountain features like these:
Without ice, what would the Rockies, the Andes, the Alps and the Himalayas look like today?