>>61179297 (OP)
There's a couple things to unpack here:
If you marry a good woman and she doesn't divorce rape you, marriage is a powerful wealth building tool because you get significant tax breaks and potentially a second income. Even if your wife doesn't work, if she's actually a legit housewife that means you have someone to cook, clean, and take care of the house. All of this is pretty burdensome to do if you always have to do it by yourself and can't share the responsibility. Being single is way better than a bad relationship, but a good relationship is way better than being single.
Married men also are just usually seen as more normal and well adjusted. A married guy with kids is more relatable to other married guys with kids. Whether or not you're married is not a deciding factor in any promotion, but it does make a big impact on how you interact with people. And that IS a deciding factor in most promotions.