The truth is that the personality of Superman has changed and developed with the times. To be honest, the good old fashioned Superman was pretty one dimensional and kind of boring. Clark Kent was the bumbling reporter and Superman was the boy scout powerhouse.
I too grew up with the Christopher Reeves Superman. The movies were fun because there were no other superhero movies. But neither Superman nor Clark Kent were all that interesting. I had high hopes for the Return of Superman movie but was disappointed when they tried to just continue the Reeves Superman.
The Kal-El and Clark Kent of the current movies is someone that I am interested in. Some thought his killing of Zod ruined the character. I saw it as making sense of the character. In his choice to kill rather than let innocents be killed, we saw why Superman is who he is.
In Batman v Superman, the way Superman reacted to Batman made sense. Without spoiling anything, his motivation for being willing to fight Batman, fit with what we know and want to believe about Superman.
The nobility of the hero and the humanity of the Kansas farm boy was all there. I can watch Clark Kent without cringing and I can cheer Superman on with some understanding of who he is.
This Superman may not be the one you grew up loving but it may be a better one.