How is that different from mutual TLS authentication?
Edit: It seems like OPAQUE just initiates mutual TLS authentication after the TLS session has already been negotiated with PKI. So it basically just allows websites to design their own login page instead of the one designed by the web browser.
Not all FOSS projects need to be profitable to survive. IOW if a project cannot survive without being profitable and it cannot be profitable long-term, then it cannot survive long-term.