I know that nowadays girls start around 18 to look to get married- maybe you can be Melamed Zecus that they aren’t ready yet for marriage beforehand-so maybe they aren’t Oiver anything yet.
Do many singles abrogate their chiyuv to get married because they’re too picky? I think so, but I wouldn’t push them into what would likely be a bad marriage.
I know of an older single girl who on several occasions was close to getting engaged. She had reservations, and spoke, each time, to an adam gadol. She was not told to simply get married because she has a chiyuv! If she had a legitimate concern, the rov she spoke to told her not to marry him!