It's not "being cautious", or "reactive sexuality", or "evolutionary burdens of pregnancy and childbirth", and yet it's all of the above.

In layman's terms, it is a relatively accurate generalization to say that men love women, but women don't love men (as much).

When women explain why they don't like being approached by strangers, they occasionally bring up the analogy "imagine if a huge gay dude tried to hit on you". It is the same as just saying:

"don't hit on women, they are not heterosexual".

Same as a man would tell a hypothetical "huge gay dude", "stop hitting on me, I'm not gay".

"But I love my boyfriend/husband": if out of entirety of female sex, only one woman caused me to feel sexual desire and romantic attraction, I would not call myself straight.

Wives have predominated (USA) in wanting divorce since the earliest available data on who wanted divorce from the 1940s. Wives have consistently reported lower marital satisfaction than husbands since the earliest available data from the 1970s. Women have been the majority of divorce plaintiffs since at least 1862.

"There are many reasons for divorce besides 'unlove'" - Exactly; same as there are many reasons people stay together besides love. Unless the opposite is demonstrated, we can assume that these two cancel each other out.

Upon widowhood, men experience significantly greater elevation of risk of suicide than their widow counterparts among women (USA 1996), especially among younger cohorts, PRESUMABLY (according to women) when men treat their wives/girlfriends mostly as "replaceable bangmaids without agency", and generally speaking, still have plenty of open dating opportunities.

Upon winning a lottery, men marry and have kids; women divorce (Sweden).

Upon promotion, men stay married; women divorce (Sweden).

(Disclaimer: footnotes saying, paraphrased, "when adjusting for systemic systems, institutional institutions, cultural cultures, and gendered genders, there is no difference", - say literally nothing, sans occasionally "when women do terrible things, it's still men's fault". These are mandatory feminist paragraphs that are required to get a study published. Without them, a social sciences study has exactly zero chance of passing a peer review.)

When committing violence, women are more likely than men to target a person of the opposite sex (USA), self-defense not included.

Most infanticide victims are male, above what we would expect from natural sex discrepancy at birth. While not all this difference can be attributed directly to women's propensity to kill boys more than girls (as many of infanticide cases are unsolved), it is known (same source) that maternal infanticide often gets misclassified as SIDS, and SIDS is widely believed to affect boys more (the source's section "Recidivism" lists multiple instances of women confessing of murdering their babies whose deaths got misclassified as SIDS). Additionally, there was (currently memory-holed) report by UNICEF showing that in developed developing (typo fix) countries, where usually women are in charge of food distribution within the household, boys are more likely than girls to have their development malnutritionally stunted, with only 4 countries being exceptions (reversed), and 2 more having equal rates. UNICEF's proposed solution was to give more food to women.

"A survey of 67 studies reporting nonpaternity suggests that for men with high paternity confidence rates of nonpaternity are (excluding studies of unknown methodology) typically 1.9%" - Translation: roughly 1 in 53 children is raised by a man coerced, gaslit, and abused by a woman into believing that this child is his, despite it not being the case. I claim and postulate that it takes significant amount of "unlove" to take a man and flush his life and legacy down the drain like this.

TwoXChromosomes has 13.6 million subscribers.

Each of such pieces of evidence can be considered weak by itself, but they combine into quite a unidirectional bunch.

DEBATE.

EDIT: To women mass-spamming the post "You don't love women, you just want to fuck them" - YOU ARE PROVING MY POINT. Thank you. Only a person with a deep unlove for male sex would see it in such a light.