Besides it being a learning project for yourself. Why should people care about it more then something like conan? I don't want to downplay your project. But you need to bring something interesting or new to table to get people interested.

Me personally I don't think that package managers will ever be a widely used thing in the C/C++ world. Both languages are mostly used in low level or close to Hardware programming. Both requiring good understanding and knowledge of the Hardware you are running on. And this is contrary to the benefits a package manager offers, which is General purpose and easy to reuse code.