I kind of doubt that. After all, plenty of people stay in the pew because they are not Catholic and know not to receive; were hungry and forgot about the 1 hour fast and so are refraining from receiving; already went to an earlier Mass or plan to go to a later Mass and received/will receive there, is not in actual sin but is perhaps choosing not to receive as a courtesy to another family member who is not receiving, in order for them not to feel ‘singled out’, is scrupulous and concerned, not in actual sin, but would rather not receive ‘in case’, is watching children under the age of reason and has made a spiritual communion and would rather remain quietly in the pew, etc.
And even if the person were ‘hey, look at me, I’m a sinner who didn’t go to confession’ in truth, so what? Would they rather be, “Hey, look at me, I’m a sinner, didn’t go to confession, but I’m receiving in mortal sin because I’m afraid of what people will THINK?”
If you stay in the pew, the ONLY thing you are conveying to anyone is, "I am staying in the pew. What people choose to speculate about or assume is their problem, not yours.
In some ways, I love being old and not caring if people ‘think’ something untrue about me.
OK, to be honest, I would care if a couple of million people thought I was a killer, or a heretic, or a bad knitter, because the odds are that with that many, somebody who could directly negatively affect my life, health, and freedom might do just that. But when it comes to a few hundred or a couple of thousand people in my parish thinking, "Oh look at that sinner who didn’t go to confession, tsk, tsk’, I’m, “whatever, people. Think what you want, it has no effect on me. If you think I’m that bad and you decide not to invite me to the Parish council or don’t give me the handshake of peace, it’s not going to ruin my life!”