They found that empathy increased across the life span, particularly after age 40, and more recent cohorts were higher in empathy

Longitudinal Changes in Empathy Across the Life Span in Six Samples of Human Development. Jeewon Oh et al. Social Psychological and Personality Science, May 20, 2019. https://doi.org/10.1177/1948550619849429

Abstract: The development of empathy is a hotly debated topic. Some studies find declines and others an inverse U-shaped pattern in empathy across the life span. Yet other studies find no age-related changes. Most of this research is cross sectional, and the few longitudinal studies have their limitations. The current study addresses these limitations by examining changes in empathy in six longitudinal samples (total N = 740, age 13–72). In a preliminary study (N = 784), we created and validated a measure of empathy out of the California Adult Q-Sort. The samples were combined for multilevel analyses in a variant of an accelerated longitudinal design. We found that empathy increased across the life span, particularly after age 40, and more recent cohorts were higher in empathy.

Keywords: empathy, life span development, Q-Sorts, personality