I don't necessarily think we are. I know that we think we are the "wisest" species on Earth, but the other species very well may think the exact same thing for all we know. The problem is that animal consciousness is too different from human consciousness to compare. For instance, there are ways in which cats and dogs are likely "smarter" than humans, but humans make the mistake of brushing their smarts off IMO by saying stuff like "Oh, well but that's just instinctual knowledge". Yeah, so is half the stuff that people think about day to day. When humans try to compare the "intelligence" of animals to one another or to ours, there is no way that we can stop using our own psyches as benchmarks. So, really what we are saying when we say "how close is the intelligence of X animal to a human?", what we really are saying is, "How similar is the intelligence of X animal to us?" The question of "How intelligent is X animal when considering the environment, desires, and lifestyle of X animal?" is not something that we can objectively measure as any human being has too much observer bias to do so.
Humans are the only animal that has chosen to alter the natural environment to create an environment of their own. We have built cities and changed the planet in ways that no other species has done. However, it's debatable whether that really makes us "smarter" than other animals. In the end, this may very well end up being our downfall as in altering the environment to suit our own needs, we have caused damage to the environment that we might not be able to reverse. This damage has already led to the destruction of some of other species and could in theory, in the distant future, completely fuck over the world entirely for all we know. Humans seem to have a greater ability to build and develop technologies than other animals yet humans aren't really able to regulate themselves and humanity is developing in uncontrollable and potentially dangerous ways. I'd argue that humans have a lifestyle and way of being that is very different than other species, but unfortunately it might not really be inherently "better" or "wiser" in the end. We don't know. Given the way evolution works, just about anything could happen when you think about it that way.
Plus, evolution is changing other species. So, for all we know, other species could evolve in unanticipated ways and so could we, these things change over time and the way that species on Earth live and what species are on Earth changes and evolves over time. There have been many cycles of evolution and species come and go every couple hundred/hundred million years or so (e.g. look what happened with the dinosaurs). How do we know that 100 million years from now, humans couldn't have royally fucked ourselves over and........ and instead of people having cities, cats do that instead and humans have devolved back to apes or be off the planet entirely. Perhaps, they've become the "advanced species" in a hundred million years and they're doing things like building cities, using electricity, voting for cat presidents, organizing political movements and protests, and flying to the moon....... and they're the ones posting questions about "why are we the wisest species on the planet?" on a philosophy sub-forum of a site about catnip. A very silly scenario of course and incredibly statistically improbable that this scenario will happen, but yet there's nothing to say that this is impossible in say a hundred million years of evolution. It probably won't, but it could for all we know.
Or humanity could fuck itself over and the next wisest species is something that never existed before. And perhaps, this species is more advanced technologically than humans will ever be. That's possible too, and probably far more likely than a feline apollo mission. Humans have only been the "most advanced species" on Earth for a few million years anyways, even if our perceptions are accurate. The Earth is over 4 billion years old, and there have been other "wisest species" at other times. As far as we know, they didn't build cities or anything but still one of the species always had to be "the most advanced'. Unfortunately, I suspect that humanity probably either after millions of years will no longer be the dominant species on the planet or evolve into something unrecognizable.