That was my belief on the etymology as well.

So why shouldn't we use that word?

Do you think it's been co-opted by sjw types? They love grabbing words and changing the meaning, which then spoils the normal use of the words. Of course, it depends on your company; if everyone in the room uses the first definition, the word effectively means that when you say it (as far as their understanding is concerned).

The present common definition I see for it basically means "blue pilled". Which is practically the opposite of what the origin seemed to have meant. I think part of the misunderstanding was organic since it may have been intended as a companion rather than a replacement for "red pilled" (theory seems backed up by your link that I skimmed), and nuance in slang can be difficult. The rest of it I'm ready to blame on co-opt efforts, but I'm interested if you have any personal insight for this.

Edit: My theory was off, as expressed further down in coversation chain. Leaving this post as is to evidence logical processing.