Rust is considered to have a steep learning curve. How much does solid C++ experience impact that curve, relative to languages that hide more of the internal workings?

I used C++ primarily for about 5 years (though I now have several Java years in between). I've been waiting for a compelling enough project to justify the steep learning curve I've heard about, but haven't run into such a project yet. Am I misconstruing the amount of work and creating artificial barriers to adoption? What would you consider compelling enough to justify the time, knowing what the cost of bootstrapping is from the other side?