There are surely many catholics out there who don’t even know Church teaching on the Eucharist. I know this to be a fact since my sister is one of them. She married a divorced man in a civil ceremony, yet I’ve observed her numerous times receiving the Eucharist, usually at funerals or Christmas (she only attends Mass on such occasions).
The problem with my sister and many other catholics is that they’ve been poorly instructed in the catholic faith. They are virtually oblivious to what the Church teaches. So no matter what this synod resolves or doesn’t, these non practicing catholics will still be in the dark regarding the faith. They don’t take religion seriously. If they happen to attend Mass, they will simply go with the crowd and receive Communion because they feel its their right to do so.