[JdeBP]

"sentience" has an additional problem that science fiction authors conflate it with "sapience".

I suspect that some influential science fiction editor made a mistake early on and it stuck. Outwith science fiction, I've less commonly come across the conflation, and people generally use the dictionary meanings, more in accord with the Latin roots, of "sentient" meaning being capable of sensation/feeling and "sapient" meaning being capable of intelligent thought.