Snoke theories have been commonplace in the Star Wars fandom ever since the lead up to The Force Awakens. You'd think, by now, all available options for Snoke's identity had been exhausted. Never underestimate the ingenuity of Star Wars fans, because this new theory could be the most creative yet. It involves subtle psychological suggestion, designer genes, and yes, Kylo Ren's obsession with his grandpa.
Reddit user thecircularblue theorizes the basis for Snoke wasn't an organic being at all. Instead, the Supreme Leader was tailor-made to encourage Kylo's romanticization of Darth Vader. Palpatine based Snoke's face on the melted mask of Vader Kylo seemingly worships in order for him to more closely associate Snoke, and, by association, Palpatine, with his so-called "legacy."
It may seem outlandish at first, but after comparing the two, there's a definite similarity in the sunken left cheek and sloped eye, as well as a barely-there jaw and crack in the top of the skull. Considering how humans are hard-wired to recognize faces, Kylo would recognize the resemblance, even subconsciously, and put some of the admiration he had for his grandfather Anakin onto Snoke and the Sith as a whole.
Not enough evidence to convince you? Consider the first Exegol scene in The Rise of Skywalker, when Palpatine was revealed among tanks of failed Snoke clones, floating in tanks. Why were they never used? Perhaps because they didn't have the facial similarity to Darth Vader's mask the actual Snoke did. Even in the Star Wars universe, genetic manipulation is a complicated endeavor, and it's difficult to get things exactly how you'd like. It's understandable Palps would have a few failed attempts on hand.
This character design could have another, deeper meaning which goes beyond a visual trigger for Kylo Ren. Just as we are hard-wired to see faces in things, we associate asymmetry with grotesqueness — the eviscerated mask and Snoke's partially-formed structure are unfamiliar and therefore evil. So while it's affecting Kylo's perception, it's also affecting ours.
The Inverse Analysis
Is this the canonical answer to "Who is Snoke?" Probably not. It is, however, a plausible explanation for that pesky Snoke question, while also keeping in mind a majorly unexplored aspect of Palpatine's actions: the ethics of the creation of life and cloning. While Palpatine likely had no qualms about playing God, the concept of a Snoke designed through trial and error to manipulate the young Solo is disturbing from a psychological point of view as well as an ethical one.