[feverdream]

Isn't that part of what it means to be vestigial? It used to serve a function, but it doesn't now.

[dwighttk]

Vestigial has often meant “we don’t know/haven’t identified what function this serves” … yet.

[Intralexical]

The famously "vestigial" human appendix actually serves as a seed vault for replenishing gut microbiota after a gut disaster, I hear.

[hammock]

Unfortunately. As with the appendix.