“What I find puzzling is that many Catholics concede that Protestant Christians CAN be saved and are genuine Christians, while being without that core teaching of the absolute necessity of receiving the Eucharist for salvation.”
“absolute necessity of receiving the Eucharist for salvation.”
That statement is incorrect as regards the Catholic Church. This is very simple - anyone who professes belief in the Father, the Son, the Holy Ghost is saved forever. The Eucharist at every mass is acknowledging the sacrifice Christ made for us. That’s it.
I'm sorry, but that is simply not Catholic doctrine. In fact, you are risking eternal damnation by spouting heresy.
“The Eucharist at every mass is acknowledging the sacrifice Christ made for us.”
There’s quite a difference between acknowledging what was done (Protestant doctrine), vs insisting Mass is in fact a literal physical participation in the actual sacrifice, right down to drinking actual transubstantiated literal blood (Catholic doctrine).