I totally agree with that. It's a wonderful stage of life when you can go learn, explore, have adventures, fall in and out of love, do some living on your own and stand on your own two feet.
I'm biased I'm sure because I personally was nowhere near ready for marriage until well after age 30. That might be somewhat unusual but I'm so, so glad that a) I waited for the right one, and b) had done a LOT of stuff before I met him, so kind of had those things out of the way and was more ready to commit to someone.
Different strokes for different folks, of course. Both my sisters married while in their 20s - one at age 22, the other age 25 (that sister met her husband-to-be at first sister's wedding, and married him the following year - how's THAT for romance!), and they have both been happily married for better than 30 years now. When you know, you know - they were both ready, in their individual ways.