Yes you could likely design an optimized modulation scheme to do this, likely some kind of bird specific frequency shift keying. You can also do any kind of quadrature modulation in the audio spectrum (original dialup used acoustic modems).
This person just didn't do that in this case. It's still a very cool experiment by YouTube maker standards though.
CookieOfFortune@lemmy.world 4 days ago
My point is that it doesn’t have to be optimal to be considered digital. Which in the general case means basically any communication channel can be digital.
If the argument is that they didn’t correctly calculate the bandwidth, then sure.