towards the 35 minute mark it gets more spicy. up to then it's almost like a monero commercial.
tldr is that they need lots of offchain information to eliminate the decoys in ring signatures
Discussion
That's way above my head. I have been in bitcoin for 7 years now. But I have never been very technical.
its an ongoing thing of course
i have the advantage of being an long time tech guy.
basically
in contrast to Bitcoin where you have a single sender that's obvious on-chain,
in monero the true spender is hidden among 15 other decoys.
that "ring" of addresses sign the transaction and its impossible to tell which of those 16 is the real spend.
originally developed for Bitcoin btw,
but never implemented, like lots of monero tech.
theres more nuance (like ways CA can maybe eliminate some of the decoys etc) but thats the basic idea.