The figure of the Ubermensh in Nietzsche's writing is not a new species in the biological sense, but a model of behavior for current people. The word "species" might appear somewhere in the writing, but then again Nietzsche loved flowery language. It just doesn't make sense that he would advocate for evolution to do the job we can do ourselves.
In Genealogy of Morals Nietzsche argues that moral rules and the values that define them are just modes of valuations: to each their own when it comes to decide whether a specific action is good or bad. Some value strength, holding one's word or pleasure, others value obediance or modesty. Nietzsche did not believe in the freedom of the will, so in his view one does not chose their own values. This part of your question (and probably JP's lecture) is I think a fundmental misunderstanding of Nietzsche's thinking.
People just like and value what they like. What makes an Ubermensh special is they don't refrain from acting according to their values out of shame or fear of being devalued by others, according to other people's mode of valuation. Shame is indeed the driving force behind what Nietsche called "slave morality", which is morality built by weak people in reaction to strong people exerting might to their detriment: "how dare they? they ought to be good to us!".
So it's not about choosing to love something or to be interested in something we find boring. First because according to Nietzsche we dont choose to love, and second because doing something boring because it's "the good thing to do" would actually be the opposite of an Ubermensh behavior. Nietzsche's idea is that powerful people do what they already love to do, and what bores them only in so far as it's part of their own goal.
Here it's important to signal that the Ubermench does not have to be inconsequential or avoid any responsibility. This is not simple pure hedonism. For exemple, one can be extremely patriotic yet not particularly like the idea of fighting a war. Yet, it might happen that when push comes to shove they have to enlist in order to protect their country even though they don't enjoy it. Another might be opposed to the war, considering it is not according to their values, and dodge the draft while knowingly taking the risk to be punished for it. The point being that they do it with a reason of their own in mind, not because they got shamed into doing it by other people.
If you're interested in philosophical lectures online may I suggest you give a try to actual professors of philosophy like Jeffrey Kaplan instead of an ex psychologist turned pundit whithout expertise in the topic.
