There’s less of a difference between the two categories.
But in any event, it’s a personal choice, and for some it will absolutely make sense. Some cultures still frown on having children outside marriage, so for a woman getting married may mean the difference between having kids or not.
Some may also decide against waiting to get married and putting their life on hold - who knows if Trump will make changes to family immigration. It would be awful to not get married for a visa and then find you can’t get one anyway, I’d imagine there’s a lot in the banned countries that are in that situation and may be regretting staying single now.
I know I’d rather have waited longer with my husband and kids than have to spend several years living in a different country from them. Each person has to make their own choice, as long as they are aware that marrying will make their wait longer (but mean their spouse/kids can accompany them when the time comes) that’s up to them.