The placement of the tabernacle is in no way incorrect. At the church I grew up in, the tabernacle was to the right of the altar. At the church I currently attend, the tabernacle is in the center of the altar, but it varies just about everywhere I go!
It wasn’t actually until middle school that I realized why people genuflected toward the front of the church, when my religion teacher taught us how to properly genuflect. Now that I am a Eucharistic Minister, I have an even more profound respect for Christ in the Eucharist, and I try to impart this respect to those around me. I do this by genuflecting and bowing at proper times during the Mass, as well as occasionally having conversations with my Catholic friends about the magnitude of the Eucharist. It’s important of course not to force such conversations, but to let them flow naturally.
As the poster before me said, if people are genuflecting improperly, it is just because they haven’t been taught properly. If you have friends who genuflect improperly, this would be the perfect time to gently impart to them some of your knowledge. Simply explain what genuflecting is and that its purpose is to reverence Christ in the tabernacle. You may speak with your parish priest if you are worried about it, though I believe God receives their good intentions and understands our fallible nature (after all, He did create us!).
God bless you and yours in this most joyous of seasons!