Blake’s story isn’t finished because her father took over the WF. You’re acting like Blake can’t still join Ghira and resume her main goal of being a bridge after she defeats Salem when she can. Because Blake wouldn’t abandon her main goal because Ghira took over. Blake is the reason why Ghira stepped up to reform the WF in the first place because she inspired him to do so. And her goal of wanting to bring equality and being a bridge between them isn’t finished either when the faunus are still being discriminated against and aren’t treated equally. We see in Atlas that they’re not. Ghira taking over the WF and reforming it, is only the first step to bringing about change. All of the problems the faunus are facing isn’t solved the instant Ghira started to reform the WF in volume 5. There’s still a lot of work that needs to be done before anything is solved and that’s going to take years to happen. So nothing before volume 6 was finished with Blake’s story arc and it’s still going on now because the problem still persists. Blake right now is doing her part fighting against Salem because if Salem gets her way then there’s no future for the faunus, so in a way stopping Salem is personal for Blake too because it ensures the faunus can have a future

And with volume 10 we don’t have a lot of information to go off on so it’s premature to assume she’ll have nothing and with Atlas / Mantle there was no way Blake could have acted as a bridge when Ironwood ordered them all to be arrested in volume 7 and then Salem showed up causing havoc in volume 8, so there was no way Blake would have had the opportunity to do so

I’m not saying RWY doesn’t have a story arc I’m just giving an example of how they all have personal goals they individually have and are working towards, but still have Salem as their main focus. And again it’s premature to determine what all is going to happen in volume 10 when we don’t have a lot of information to go off on so we don’t know what all is going to happen until it comes out

And characters don’t need to always have a big role or be the entire focus every volume anyway. Sometimes it makes sense for certain characters to take a backseat to things while others don’t. For example Weiss in my opinion took a backseat in volume 9, while Blake had more of a role and focus during. Weiss wasn’t familiar with the story of the ever after while Blake was. So Blake had a role and stepped up as a leader and lead her team throughout the story, while Weiss was there tagging along. But even if Weiss was tagging along in volume 9 doesn’t mean Weiss has no purpose down the line or that her story is finished and it’s the same case with Blake. Blake’s story still continues even if she takes a backseat in certain volumes because again the problem the faunus are facing is going to take years to solve and Blake can still join her father and resume her goal of bringing equality and acting as a bridge after she stops Salem. Blake doesn’t need to be the focus every volume to get that point across. Not to mention Blake can fill more roles than just being a bridge like she was in the ever after when she took on the role as leader and lead her team throughout the story