Does anyone else think this seems like a lot more "pseudo" than "science"? Is it specifically supposed to be more of an exposé of this one guy's subjective view? Why does it focus on just this one mathematician? The author briefly touches on Max Planck's work, but then seems to conflate objective reality with human perception?
The key insight (that older people count out seconds faster) is based on experimental science. The rest is more speculation.
FWIW, I'm convinced that seconds felt slower when I was a child, and they now tick up faster than they used to. Obviously there's no way to measure this, because this is my perception, not measurable reality.
Larger brain need more time to propagate waves, so smaller brains have advantages. Also, with age our brains become more convoluted, which makes wave propagation even slower. Fly sees world at 400Hz, human: at about 16-20Hz.
Try to play games, which requires fast reaction and deep thinking at same time, and speed of your brain will increase a bit.