I also agree that I don't see the point of continuing to eat something you don't like in order to get used to it. I don't like coffee, olives, alcohol, and several other things people tell me I'll get used to. Life's too short to spend it that way.
I think that point is missing some significant aspects of the human condition.
If we simply relied on our base instincts (i.e., not
developing a taste for anything, but just sticking with the tastes we have innately), we'd be drinking sugar water or blood. I'm not necessarily knocking folks who like the things that our base instincts drive us to eat, but the reality is that we generally derive substantial satisfaction from tastes that we develop, beyond our base instincts.
Beyond that, I think anyone who claims that they don't develop tastes, and instead only are driven by their base instincts, are not thinking it through. We generally don't think about how much of what we
like is actually a reflection of a developed taste rather than a base instinct. However, all you need to do is go to WDW, on the Dining Plan, with a 10 or 11 year old, and you'll get a very clear demonstration of the phenomenon, since, if you're anything like me, you'll get this nagging sense of "oh gosh" realizing that you've spent all this money on 10+ year old dining credits for your child, only to have your child turn up their nose at practically every one of the most favored items on each table-service restaurant menu. Children naturally develop an appreciation for more and more foods as they grow older.
The question is whether we decide to to stop growing our appreciation. There is nothing wrong, necessarily, in doing so, at least within a relatively narrow area like food. My SIL has a very limited palate. She therefore loses out on the opportunity to derive pleasure from the enjoyment of myriad culinary options. That's okay. However, it is clear that her decision to restrict her tastes to the foods that she ate (basically) when she was 10 years old means that she is excluded from a whole host of pleasures that many of the rest of us have access to. By the same token, I'm sure she derives pleasure from some things, having nothing to do with food, that many of the rest of us don't. Presumably, it's enough.
What benefit is there to not trying to develop new tastes? The mechanics of developing a taste are such that you start out by not really liking something, and then it's okay, and then it's better than okay - so much better that the negative aspects of that short period of time that you didn't really like it is more than worth it. However, that's not the way it always works; the "investment" in trying to develop a taste for something doesn't always pay off I suppose.
In the end, though, I cannot help but wonder what value there is in our stopping the growth of what we appreciate, even within a relatively narrow area like food. Life is short, but not so short that we can't afford to spend a little bit of time to earn greater returns on that investment later. I prefer to look at life as a vast library of experiences, and see great value in trying to work my way through every kind of book.