I haven't read much on monero / this algorithm, so I'm not sure if it's particularly meaningful, but wikipeda references that being the case for most of 2017-2018 and then the algorithm was changed.
The Wikipedia article is incorrect, Monero still uses ring signatures. Bulletproofs are used as efficient range proofs in RingCT to hide the amount in transactions.
Honestly, comments like this are why I stick with hacker news.
Thank you! There's a lot of difficult-to-google info locked up in comments like this, and I truly appreciate the effort spent replying to randos like me :)