This simile is utter nonsense from the outset. Pi doesn't change. It's the same regardless of who you are, whether you're a human, a dragonfly, or a rock; it's the same whether you're measuring in planck lengths or astromical units.

Language is the utter opposite - it constantly evolves and changes, with new words entering every year and grammatical patterns changing over time as well. The only way to stop a language changing is basically to stop using it.