u/Losaru

Just a thought and I'm probably not the first to come up with this, but I think that the reason why Homeworld eventually gave up on the Rejuvenator wasnt just because a Gem could regain their memories, but also because of Rhodonite; or more specifically, her backstory.

This thread is already spoilers so I'm not going to hide this; Rhodonite was rejuvenated 17 times at her Morganite's command according to "End of an Era" where it was revealed. And while this would make her Ruby and Pearl default to their original programming, it wouldn't last. Each rejuvenation was because Ruby and Pearl fell in love and fused again. After the 18th time, she finally had them replaced.

I like to think that because of these failures in particular, Homeworld decided to give up on using the rejuvenators as they not only can be reversed by making a Gem regain their memories, but because a rejuvenation cannot stop fate. No matter how many times, Ruby and Pearl would always end up falling in love and fusing into Rhodonite. If the rejuvenator couldn't stop such an upset, why bother using them. As to why they weren't simply destroyed, I think the scythe versions were kept in Pink's memory and the embedded ones such as at the Reef were simply kept as aside from the Rhodonite situation, Shell probably didn't need to use it as often as it only presides over Pearls.

So that's my lil crackpot theory. Hope you enjoyed.