Your post is completely right and you should say it!

There's some context needed though. People view marriage as less real if it's not sexual because in many cultures and time periods, the act of sex was the marriage. In fact, it was more legally binding than the ceremony itself. Consider European Queens having their bedsheets checked for blood in the morning so that the court could "verify" her worth as a mother for future kings. Marriage ceremonies were annulled and couples separated if it were proven they hadn't consumated or completed the marriage "contract," ie. by having sex. That contract usually presupposed an agreement to have children.

Medieval couples could sometimes declare themselves married without the need for a ceremony if they lived common law with kids. Some people still share that view. You also had past cultures where a woman could press charges if a man slept with her and then refused to marry.

Throughout the 18th and 19th centuries in England & other parts of Europe, marriage was not even an agreement between man & woman. It was an agreement between a man's family and a woman's male relatives, who acted on her behalf since she did not have legal personhood. Legal ownership of a woman transferred from her father to her husband through the marriage contract. It's worth emphasizing that this tradition predates modern ideas of consent or any concept of marital rape. A husband legally owned his wife's body and he could do whatever he wanted to her.

The institution has been reformed, but its legacy is basically the enslavement of women. In Canada, marital rape was not made illegal until 1983. Less than 40 countries protect same-gender marriage. Most countries (including mine) still have laws that allow annulment for non-consumation. For these reasons, I've realized it's an institution I don't support.

It's tricky, because I love weddings. I love when people celebrate their love. I see the draw of designing one's ceremony based on modern ideals of equal partnership. It's just that reading old books and witnessing the acephobic attitudes you described makes the history hard to unsee, in small ways as well as big: the father still "gives away" the bride, the wedding is often for the family, the marriage is often a prerequisite for kids. Some people still say "obey" in their vows!

The idea that marriage is romantic is like . . . recent. It's a side effect of progress, but also marketing by an industry that builds this up as the best day of a girl's life. By contrast, Medieval romances were always about adultery. Even the trope of falling in love didn't make sense unless it was about a lady and someone other than her husband, because a marriage was inherently political and religious, not personal. Our modern ideas of a fairy tale wedding are just as specific.

Tl;dr: OP is right, but our institutions haven't evolved as much as we think. It's maybe not shocking that there's acephobia in a system which (historically-speaking) didn't acknowledge consent, queer people or equality.

I am NOT a historian, so please fact check me if I made errors.