Frankly it sounds like you need to make this happen. I don't know your company culture but at places I've worked Staff+ engineers aren't meant to wait around for permission to be catalysts and mentor other engineers.
But at the moment I have work to do and deadlines to meet, so it's a hard sell to suggest stepping back from active development and focusing more on incubating our less experienced devs. Even though it's better in the long term, and my manager would even agree on that, important short term projects just take priority.