First of all, when I speak about sin, I only focus on my own, and I have quite a lot of effort dealing with them already, so really not much time left to focus on others.
Secondly, sacrilege of the Eucharist according to Canon Law brings the penalty that I have mentioned. The reason I point it out is to show that in fact we cannot consider someone who is unsure of being in mortal sin but still partakes of the Eucharist as committing such a grave act. Sacrilege is a whole other business!
Speaking of not focusing on others, it is perfectly possible for someone not to be in a state of mortal sin every week, or to confess during the week. Ultimately, though, it is a matter of pastoral attention to educate the faithful on the importance of the proper disposition for Holy Communion. The fact that (worst case scenario) nobody goes to confession regardless and still receive communion does not make this valid, or good. It is wrong. And it is better to thoroughly examine our conscience and receive the Sacrament of Reconciliation if we think we may be in a state of mortal sin, than to partake unworthily of the Body of Christ. Not that anyone is worthy of this great mystery, of course.
My advice is to be very careful in understanding what the Church intends for “full knowledge”, rather than applying our own interpretation. We speak of “being conscious of a grave sin”. And a good examination of conscience will reveal if a sin was grave or not.
Consider what the Catechism teaches us.
1385 To respond to this invitation we must prepare ourselves for so great and so holy a moment.
St. Paul urges us to examine our conscience: “Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. Let a man examine himself, and so eat of the bread and drink of the cup. For any one who eats and drinks without discerning the body eats and drinks judgment upon himself.”
Anyone conscious of a grave sin must receive the sacrament of Reconciliation before coming to communion.
I don’t understand the fear for confession. The saints confessed weekly! In the world we live in, we can’t possibly be less sinful than them

So perhaps we should examine our conscience more profoundly and not be afraid to confess, even biweekly or weekly, even if we feel we only have venial sins to confess.