XChaCha20-Poly1305 will probably never go out of fashion. Argon2 is only making itself in, phasing it out will take decades. OTOH you have a point in that the

XChaCha20-Poly1305 will probably never go out of fashion. Argon2 is only making itself in, phasing it out will take decades. OTOH you have a point in that the author's implementation PBKDF2 is being used, and that should already have retired a decade ago.