It's very modern work. It has the rhythmic assymetry, shifting accents of Rite of spring. It has the overlapping ostinato patterns over a harmonic static pedals similar to Rite of Spring. It has harmonic progression that is not traditional and that doesn't resolve or progressed but is just there similar to Debussy. It also has modern orchestration technique such as the trombone glissandi.
Now traditional 20th century music history would say that this was an important work where Stravinsky used the techniques of the Rite Of Spring and married it with 18th century styles of music creating a genre of music called neoclassicism. That this is one of Stravinsky silver work, a highly significant and important and innovative work in terms of synthesis and important within a specific subgenre of classical music but not an overly important piece of music that revolutionised classical music unlike the "mindblowingly original" The Rite Of Spring
However I'm sure in a science fiction parallel universe where my version of music history is written . I would say that Pulcinella is perhaps the most important work of the century and would be the model where all future composition was based on instead of The Rite of Spring.
In my hypothetical fictional parallel universe. Rite Of Spring would have been considered a failed experiment. His innovation of juxtaposition, rhythmic assymmetry overlapping ostinato resulted in an incoherent piece of music and evidence that these compositional techniques has no real function and utility in music. It was only when Stravinsky used those same compositional technique and combined with melodies written in the 18th century that he showed that those compositional technique could be consistent with the classical ideals and with creating music that reflects truth and beauty while being exciting with it's modern techniques.
After all what is more praised worthy, creating a piece of music with original compositional technique or creating a piece of music demonstrating the strength of a compsoitional technique and demonstrated why the technique needed to be developed in the first place.
Rite Of Spring would be placed in the correct context of a failed musical experiment that was rightfully booed on premier but at the same time demonstrate the saying "failure is the best teacher" where he used that failure as a learning experience to create his career defining masterwork of Pulcinella.
alas music history isn't written by me