That's not the part that's pseudoscience. The pseudocience part is that the illusory beat can train your brainwaves to xyz frequency using binaural beats.
Anyone with stereo earbuds can see that the binaural beating effect is in fact real and easy to document by removing one earbud and hearing a solid unchanging tone until they put the Other back in, so long as two similar tones are played who's destructive interference between one another would in open air create valleys of 0 relative amplitude. Those valleys are the beats.