That was never a serious character, it was practically "The Batmen of many nations"
You want a character to succeed? Don't put them in another character's shadow and then cast them off into no readership land without the slightest link to relevance.
That's how they're killing Red Hood, and he was a freakin' Robin!
The way to go is like with Miles-Spider-Man, first there's the vacancy to fill, then here comes the replacement hero, do they succeed? No. They struggle because they're the underdog, but like Rhodey in the IronMan suit or Dick taking over as Batman they give the audience a chance to see them earn the job.
Once they've proven they can do the work then bring back the main and the former underling has now been elevated to an equal.
That's how War Machine became his own character, that's how Nightwing graduated from being a Robin, that's how Miles became the second Spider-Man.
It's a formula that works.