All of computing reduces to "just ones and zeros." In light of this let's just dispense with the decades of verbosity and libraries' worth of extraneous elaboration.
They are just saying the person they are no longer reflects that. Because people are continuously evolving, but posts online are frozen in history without context.
There are things I did in kindergarten that I no longer identify with, but that doesn’t mean they were wrong at that age or for the world at that time.
Christ, that was a grandiose article to read. To compare yourself to Lord Byron and to talk about one's legacy really screams "Hello, I am a narcissist."
Take comfort in the contributions you have made to projects bigger than yourself will be incorporated into maybe some of humanities greatest works.