I've been professionally animating for years in the U.S. for J.C. Staff and BONES so basically anime as a lead animator on Shakugan no Shana, KissXSis, etc... I've animated some stuff for Disney but I wasn't lead sadly only the "elites" are leads within Disney lmao. I always found that weird. Anyways I feel like the basic principles are so important even anime uses them but very subtly since anime is mostly static for the most part with there movements. I mean when I worked on said series we animated 24FPS but would hold frames between two frames and even up to four sometimes. We hardly animated on ones unless it was for fight scenes and even then they are usually the ones that use the principles the most with smearing/smudging as well as squash and stretch.
For example say if a character was swinging with a sword doing full 360 towards the camera there is only three to six frames actually in the whole sequence but looped for two or three spins total but to make it more convincing we smeared and squished the frames and even use some stretching to heighten the action. Its very subtle but its there and it gives a convincing fight scene.
