Genres

Technical deathcore is named such because they come from the genre of death metal which evolved into deathcore and they also aim to be as technical as possible. They also still keep their music to have a purpose. I asked the band personally what they thought their genre was and their response was as follows: “We kind of think genre classification has gotten a little ridiculous in the metal scene so we call ourselves aliencore in a kinda satirical kind of way. If you want to be more exact tho we would be called technical deathcore” -Lucas Mann(Rings of Saturn guitarist).
As a twentieth century virtuoso, Rachmaninoff was also are very technical in this context, where I am speaking of a composer rather then a violinist or pianist (even though Rachmaninoff is also a virtuoso on the piano). The piece is a concerto so it's genre is predetermined and with no composer to ask we cannot know if Rachmaninoff wanted it to be anything different then what we call it today.