I wouldn't say that.
Where something like ping might have a legitimate role is in some application none of us (reg commentards here) has thought of. Such things may be out there, without us ever having encountered them.
We can draw analogies from the past. For example, when Sun first came out with the (Java) applet in the mid-1990s, they had some silly/pointless demos ("duke" or something?). Lots of third-parties also used it to produce toys and eye-candy and probably cat videos, and it was widely dismissed as fluff. Meanwhile some of us were producing serious applications for the real world: in my case, providing interactive access to explore satellite image datasets, including some quite sophisticated GIS and visualisation tools.
But obviously that's a specialist area, and most web users would never encounter it.
Hence my question above. I can contrive legitimate use cases for this ping. What I struggle to see is a use case that isn't at least open to abuse and more-or-less sure to be used abusively if released into the wild. But I wouldn't dismiss it just because my own imagination ain't what it used to be.