The mistake is to think that Yeshiva is where you learn anything you’d ever need to learn. No. Yeshiva is where you are taught the skills to be able to learn on your own.
Most Yeshivos do teach some Nach, so that we get to know and recognize what it is all about. And then the focus is on Gemara, Gemara in depth, Halacha (maybe not enough), and a sprinkling of Hashkafa. These are things that require being taught and require spending time, especially youthful time.
Whenever you have the time to do so, please do learn Nach. A friend of mine had this idea that whenever a Gemara quoted a Pasuk from Nach he would look up the entire Perek. When I was in Kollel I began my day with first learning some Nach. No new skills required for that.