Why are we letting elderly (supposedly) celibate males who are assumed, because of their chosen path in life, to NOT have any close, intimate relationships with other humans : and especially NOT to have physical intimate relationships : to be the arbiters of who should and shouldn't be in such relationship, especially those sanctioned by society, such as marriage? What experience of such relationships do they base their dicta on? Where is their credibility? Upon what information do they base their understanding? Especially when they pontificate about homosexuality and homosexuals. Contemporary developmental psychology and reproductive science, or 3000 year old middle easter understanding of human reproductive biology?
I don't know about you, but I do not accept the medical understandings of millennia past as the standard for the medical care I choose. I do not accept the understanding of Abraham's time as the standard for the causes of illness. (I prefer the germ theory to the wrath of God theory, don't you?) I do not accept that adolescents with a bad case of acne should have to leave home and live outside the city gates : never being touched or touching anyone. That's because I do not accept the misunderstandings of 200 centuries ago as having any relevance to contemporary medical practice. It is the same with human sexuality. Therefore I do not allow credence to the unacceptable ignorance on the part of church leaders or anyone else, for that matter. How about you?
I prefer the evidence-based view that homosexuality is normal mammalian behavior, and hence part of the spectrum of normal sexuality and sexual behavior. A small proportion of humans are born with brains and endocrine systems such that they will prefer sexual partners of the same sex. Contemporary science informs us that this is so. To require people who are born that way to change themselves by force of will because most people are heterosexual makes as much sense as to insist that all blue-eyed people should change their eye color by force of will because most humans have brown eyes. It is nonsense and denies God the right to create whatever God does create.
All of us humans have a need to love and be loved, to live in community, to belong to family, to "village", to society. Some of us desire to have and to raise children. Sexuality has nothing to do with it. It is human. To deny any group of people that basic human right is ignorant and cruel : perhaps even evil. I believe that the Catholic church's position on marriage denies these basic human rights to homosexual people.
Marriage is a social contract, which can have a profound meaning for those who choose to marry. To insist as the church does that marriage is for procreation, raises the question of childless marriages. Does this mean that partnerships where children are not possible cannot be a marriage? What about partnerships between infertile couples? Should someone who for physical/medical reasons can never be a parent be denied marriage? Should women past menopause be denied marriage? What about couples who feel the world is no longer a safe place for children, and decide not to have children? Why are our church leaders not jumping up and down about such partnerships? Beats me : if fecundity and fertility are essential criteria for marriage.
My own view: a marriage (in my country, Australia) is usually between two people who love each other, who want to live together, and who may or may not want to raise a family together. Again, in my view, if both people are single, there should be no impediment to their marriage. Their gender is irrelevant. Single elderly men should have nothing to do with the decision of two people to marry.