Thats actually not true. Every single feature shown in tech trailers is in the game [except for tessellated frog]cryteks "tech trailers" that have released alongside each crysis game are not representative of the actual game. the one you linked is sort of an exception because its mostly console footage which is somewhat representative, but the single pc scene in the beginning is well beyond anything in crysis 2.
Crysis 2 DX 11 Ultra update trailer
https://www.youtube.com/watch?v=hVGNWnY_GIs
Crysis 3 Tech Trailer
https://www.youtube.com/watch?v=JWvgETOo5ek