The Short Version
This claim is false. While Abyssinians are widely regarded as one of the smartest and most trainable cat breeds, no scientific study has ever demonstrated they learn tricks faster than all other breeds. Multiple sources highlight Bengals, Cornish Rex, Devon Rex, and Siamese as comparably quick learners. Veterinary experts also emphasize that trainability varies more by individual cat than by breed, making the absolute superlative "faster than all other breeds" unsupported.