PS: Bringing up straw man arguments is not part of meaningful dialogue.
And once you’ve done that—would you agree that, by the “reasonable” standard that you are touting, that most developed countries including the United States are “utopian” in the sense of solving the problem of hunger? If not, why?
I'm sure you meant something more realistic and attainable. But that's not really what anybody means by utopia, because by that standard, much of the world is arguably already living in it compared to the ancients.
We don’t have a vast surplus of food by accident. A vast number of people devoted their lives to improving the global food supply. You can read many peoples accounts of trying to build a better world and pretend they where not aiming for utopia, but only if you also ignore what people mean by the term.
Clearly, we think of utopia as more than just sufficient food, the rule of law etc etc, but just because you are used to a better world does not mean those people achieved nothing.
PS: Consider what the world would be if everyone in history said utopia is unobtainable, so let’s burn the world.
That is also an "arbitrary metric": you've set the rate of "people not starving" to 100%. That's what it means when you say "the end of starvation", rather than "reducing starvation" or "minimizing starvation". If you want to end starvation, that means 0 starvation and 100% non-starvation. Not a single person anywhere on earth is starving.
Let's think realistically about what this means. You can probably get a few nines pretty easily, but to get all the way to 100%, you also have to make sure nobody is willing or able to go on a hunger strike, or suffering from anorexia, or in need of a competent caregiver (in cases of severe disability). You have to make sure that there isn't a parent anywhere on earth who neglects their child to the point of starvation. You have to make sure that someone is checking in on every elderly shut-in in the world, in case they've fallen and broken their leg and can't reach the kitchen. Sometimes people starve to death when they're lost at sea or in the wilderness, so now you have to achieve 100% success at search and rescue across the entire world.
And this is exactly my point. I'm sure you didn't mean all of these implications by "the end of starvation". I'm sure you meant something more realistic and attainable. But that's not really what anybody means by utopia, because by that standard, much of the world is arguably already living in it compared to the ancients. But that's not because anyone had an a priori utopian vision that they put into practice; it was through a process of gradual and incremental change that will continue as long as humanity exists. And part of that process is that there will always be perceptible imperfections.