I think it's best to understand Nietzsche's Ubermensch through vector spaces. A vector is an object with both magnitude and direction, represented as an ordered list of numbers. A vector space is a mathematical structure made up of vectors that can be added together and multiplied by scalars (numbers), and the results always remain within the space. The space has a certain dimension, 2d, 3d, 4d, ... Nd. The dimensionality of the space is defined by the "basis," for a 3d space: [1,0.0] [0,1,0] and [0,0,1]. When a linear transformation is applied to a vector space (like rotating, scaling, or shearing), eigenvectors are the special vectors that don’t change direction under that transformation. For a good introdution to linear algebra, watch 3Blue1Brown.
Humanity is one big vector space, where every human is a vector. This vector-space is described by "basis-souls" which are just different "kinds of guy": a Christian, a Hindu, a priest, a warrior, a king, a courtesan, an engineer, ... It's true that everyone is a unique special snowflake, but these are all contained within the space decsribed by these basis-souls. When people complain that "everyone is the same" - what they really mean is that there aren't that many "kinds of guys," i.e. the dimensionality of humanity is extremely low. The office, the factory, and the modern military all demand a certain kind of man to keep the lights on. Anyone with too much of the prophet or warrior within them will never survive in the modern world. A company cannot function if one day its employees are diligently working, and the next they disappear into the mountains. Modernity excludes and exterminates these souls and breeds a new kind of man (really a farm animal) to serve it.
The telos of modernity is to compress all of huamnity into a one-dimensional vectorspace, where everyone is a copy of a copy of a copy, like an ant colony. This is the so-called "bug man"... World population has never been higher and yet the number of unique human souls has never been lower. In the 19th century, there was more diversity East of the Mississippi than exists across all of NATO today. There were tribes of warlike plains indians until the 1870s. There were native German speakers in Texas and Ohio until the 1970s. I don't even think they speak French in New Orleans anymore.
This is not just a Western problem. Every city on Earth feels the same. Every year, more Mongolians are giving up their ancestral way of life, and living in stationary Yurts-shantytowns on the outskirts of Ulaanbaatar so that they can work in factories. Even Peruvian peasants that speak quechua have smartphones with TikTok. Farmers and pastoralists all over the world are hesistant whether to follow their ancestors or join the herd. The armies of the world are larger than ever but the number of armies themselves are in the dozens. The vector space of humanity is losing dimensionality every day.
Furthermore, this is not just a huamn problem. The world is greener today than it was 100 years ago, but the kinds of green have been drastically reduced. An invasive species can reproduce millions of times in a ripe environment, both increasing the quantity of overall life while reducing the dimensionality of life. Environmental regulators understand that to protect endogenous diversity, you must keep foreign species out! If only they would listen to themselves when it came to human biodiversity... Real diversity requires fences and borders.
So what is the Ubermensch, or EigenMan? The EigenMan is the solution to and enemy of modernity. The EigenMan is someone that and adds dimensionality to the vector space of human souls. He creates values, behaviors, he listens to and follows no one but himself. He is orthogonal to the everyone else, and for this modernity wants to destroy him. He is man separating and speciating into a new being.