Why didn’t [character] just use [plot device] to [do something] in the first place? [Thing] wasn’t needed, and so [Other Thing] was a waste. It makes the characters seem not that bright.
I can’t be the only one to see how potentially problematic these suggested changes are.
That’s what I’ve been saying to most of your arguments, Jar Jar! Haha.
But to answer your question, the idea is that Rey needs to embrace her inner Dark Side in order for the dagger to work, and she only learns that after getting the instructions that 3PO translates from the dagger. If she just immediately decides “Imma use the Dark Side here,” there goes her inner conflict.
Sade, very good point. If this thing was made exclusively for Rey, that’s a whole new can of worms I’d rather not open up.