It's mostly what heliodex said, that it's a copypasta when ppl need big text. There's also a compression meme around the bee and other movies (on yt: bee movie in 10s or it gets faster everytime X). But unlike i thought in the beginning it's not a zlib specific joke.
It's not really because it's "in audio range" but rather "in a range which your phone speaker can transmit" which "happens" to be in audio/hearing range we can mostly hear for obvious reasons.