Shared Communion With Protestants Would be Blasphemy and Sacrilege
Rev 18:4 And I heard another voice from heaven, saying, Come out of her, my people, that ye be not partakers of her sins, and that ye receive not of her plagues.
Yes, sorry, I can see how it appears insulting, but it’s not toward the receiving non-Catholic.
From what I know (and someone please correct me if I don’t state this well), the blasphemy and sacrilege is not committed by a non-Catholic receiving the Blessed Sacrament. If that would happen with good intentions, it’s supposedly simply not what God intended, and the sacramental part is gone; I’m not sure who the blasphemer here is, but it’s not the receiver.