First of all your premise is questionable given that Jesus himself appears in the flesh and blood every single day at every Mass in the world. Billions and billions of appearances by Jesus. He’s also at Eucharistic Adoration. So he’s appearing daily at the local parish. Does he really need to appear outside of that, when the faithful know where to go see him and visit him “in person” as it were?
Second, if you are talking about apparitions/ locutions not involving the Eucharist, there have been many apparitions of Jesus, but the Church is highly unlikely to give an official approval to a purported apparition of Jesus. They are more likely to canonize the seer and say nothing about the apparition/ vision/ locution, and so we have many saints who at some point saw or heard Jesus but the Church has not granted approval to their personal apparitions specifically. There are only two Church-approved apparitions of Jesus: the Sacred Heart apparitions to St. Margaret Mary and the Divine Mercy apparitions to St. Faustina. By contrast, the Church is much more likely to give official approval to a Marian apparition, and in some cases (such as Our Lady of La Salette) has officially approved an apparition of her that was viewed by people who did not become saints, have no active cause for canonization, probably won’t become saints in the future.
So it’s not a matter of Mary appearing more than Jesus, it’s a matter of a higher threshold for Church approval of apparitions of Jesus.
I posted in Catholic News a few days ago about the cause for canonization of Rhoda Wise, a housewife who reported seeing visions of Jesus in her home. She didn’t report seeing Mary, which makes sense because she was a recent convert from Protestant evangelical faith, and while she prayed the Rosary, she did not have a great devotion to Mary. We hope her cause will progress and that she will be beatified and canonized, but I don’t expect the Church to approve her visions of Jesus specifically.
I’ve also noticed that the Miracle Hunter website, which is the main resource for looking up apparitions and Eucharistic miracles, does not do a good job of capturing reported apparitions of Jesus. There’s no category for apparitions of Jesus other than Eucharistic miracles (i.e. consecrated hosts that bled or were found to be human tissue). And some apparitions of Jesus that were reasonably well known at some point in time are nowhere to be found on their website. I have a medal of the Miraculous Crucifix of Limpias (in Spain) which used to belong to my husband’s Catholic grandfather who likely obtained it back in the first half of the 20th century. The crucifix reportedly came to life in front of members of a parish, and it was famous/ revered enough to be put on devotional medals given to people in USA, and is listed on the Miracles of the Church website, but Miracle Hunter doesn’t list it. I wrote to them about it and got no response.
So Jesus definitely appears daily in the Eucharist, but also appears in other places as well. The Church and others just don’t go rushing to approve and promote the non-Eucharistic apparitions of Jesus.