Im gonna have to disagree with you. We ow his legacy and character success to Marv. Nightwing used to be super popular and a household name back when he was created. NTT was the series and Nightwing was its main character. NTT turned things around for DC Comics all by itself. It wasnt until bat editorial took over that Nightwing began to downgrade in character and erase everything that made him popular to begin with. Nightwing has never been compared to Cyclops. Nightwing was always intended to be the Spider-man of the DC world and never got the chance to reach those heights because Bateditorial. Its just the truth.
Also, Superman is one of the highest selling characters in existence. Batman gets pushed because he has more content, but Superman sells quite a lot and lots of people known him by name. ITs not just about Batman and i really wish people would stop it with the comparisons. DC really needs some new content because eventually, Batman isnt gonna save it from crumbling. DC hasnt been a top seller in ages and lots of writers are leaving for their own ventures. The comic industry as a whole needs to change. Nightwing's success is outside batfam. Its why Dick Grayson is still synonymous with Robin in Teen Titan stuff. Lots of people dont even know that Dick Grayson = Robin = Nightwing. Its because DC never promotes him as Nightwing outside comics and select content. To Batediotiral, Dick will always be a robin and thats why he is treated that way.