(The statistic in the title is taken from this article, which rebuts the common belief that 50% of first marriages end in divorce. My actual probability is probably even lower due to favorable demographics.)
A lot of folks try to dissuade other folks from getting married by pointing out the high divorce rates. Even a 30% chance is pretty troubling at first glance. But this statistic lacks a control group, i.e., what percentage of people who are in long-term relationships but never get married end up breaking up? I have no reason to think this number would be any lower.
My experiences with friends suggest that divorce is unhappy, but it doesn’t seem worse than breaking up with a live-in boyfriend or girlfriend. Many of these marriages die a humanely quick death (see the above article), so people get divorced before having kids. In those cases, it’s bad but not life-altering. Divorcing with young kids is a nightmare, but again, would it be any better if the parents were unmarried and ending their relationship?
So go ahead, get married. Probably can’t hurt.