The fullness of the Christian faith resides in the Catholic Church.
The Catholic Church doesn’t do “replacement theology”. The Church originally consisted entirely of Jews, who heard and believed the Gospel. Soon afterwards, gentiles were “grafted on”, through baptism and the other sacraments, so that, in Christ, they too are heirs to God’s promises to his people. The Jews of today are beloved by God but are alienated from him, as John the Baptist and later Jesus repeatedly had warned.
Your opinion of what religion’s apostate is just that — your opinion — unless you enjoy authority from God to speak definitively on the matter. Is there something special about you that we should know?
He/she SAID it was his/her opinion. What more do you want?