The term "long legacy" refers to something that has existed, had influence, or been remembered for a significant amount of time. It highlights the enduring impact or imprint left by someone or something from the past. Full definition
The selection was based on the lab's long legacy of research into materials under extreme pressure and temperature environments. (carnegiescience.edu)
Scientists had known droughts could damage tree tissues, leaving a drought legacy, but they didn't know how long the legacy lasts. (sciencemag.org)
They tend to be part of long legacy franchises, and they rely too much on assumed knowledge about control interfaces and game conventions. (theguardian.com)