Here we go again with all kinds of unbelievable stuff. I will go ahead and keep most of my own thoughts to myself, as usual - but I did want to at least call attention to the most obvious bits that seem easily understandable.
In particular I wanted to draw attention to the head which has been featured in many photos:
And in particular - note the stylized lips, as well as the stylized brow/nose combination. It almost seems to have a hat or headwrap shape combined with the brow as well. These forms are far from rare in terms of sculptural art - but it would certainly be a mistake to simply call them UNIversal, or anything else which hand-waves away the significance of the art style.
The reason for investigating this would be the more well-known site of Tiwanaku:
Which also displays heads of a similar if not the "same" art style. In particular, the lips and brow/nose combo, along with the hat/wrap - which is clearly spotted on some heads - but not all of them. Also, something which is very important is that the heads seem to be "installed" as extra pieces rather than carved as part of the original wall. Note that some even have clearly been mounted from the back, and stick out from the wall just as the Karahan Tepe head is doing.
In particular it seems strange to see the EXTREMELY weathered and eroded heads which are also on display along with other (much less aged or eroded) heads. Again there are heads of wildly divergent art styles on display as well - some appearing to represent non-human or partially-human forms. This seems to indicate a "collection" of heads, possibly from many different times and places.
Tiwanaku is theorized by some people to be an ancient "meeting place" for many cultures, or something to this effect. It may be worth investigating these ideas in much more thorough ways given these specific data points.
The other connection would be the anthropomorphized pillars commonly referred to as "The Atlanteans", which also display the same style of head:
Along with this - we know that the pillars of Gobekli Tepe also represent human forms (as well as the full-size Moai of Easter Island) - albeit in a much more abstract way. However, there is a legacy form inherent in all of these "man pillars" - which is namely the display of hands in front of the belly area.
In particular I wanted to draw attention to the head which has been featured in many photos:

And in particular - note the stylized lips, as well as the stylized brow/nose combination. It almost seems to have a hat or headwrap shape combined with the brow as well. These forms are far from rare in terms of sculptural art - but it would certainly be a mistake to simply call them UNIversal, or anything else which hand-waves away the significance of the art style.
The reason for investigating this would be the more well-known site of Tiwanaku:



Which also displays heads of a similar if not the "same" art style. In particular, the lips and brow/nose combo, along with the hat/wrap - which is clearly spotted on some heads - but not all of them. Also, something which is very important is that the heads seem to be "installed" as extra pieces rather than carved as part of the original wall. Note that some even have clearly been mounted from the back, and stick out from the wall just as the Karahan Tepe head is doing.
In particular it seems strange to see the EXTREMELY weathered and eroded heads which are also on display along with other (much less aged or eroded) heads. Again there are heads of wildly divergent art styles on display as well - some appearing to represent non-human or partially-human forms. This seems to indicate a "collection" of heads, possibly from many different times and places.
Tiwanaku is theorized by some people to be an ancient "meeting place" for many cultures, or something to this effect. It may be worth investigating these ideas in much more thorough ways given these specific data points.
The other connection would be the anthropomorphized pillars commonly referred to as "The Atlanteans", which also display the same style of head:
Along with this - we know that the pillars of Gobekli Tepe also represent human forms (as well as the full-size Moai of Easter Island) - albeit in a much more abstract way. However, there is a legacy form inherent in all of these "man pillars" - which is namely the display of hands in front of the belly area.

