The video you linked actually inadvertently explains why Monero is untraceable. I made a YouTube comment explaining why

Replies (4)

I replied to your comment, looks like you misunderstand how monero works. You said stealth addresses are used once and never seen again but in reality they appear on the blockchain multiple times: when the recipient receives money, when he or she spends that money, and possibly multiple other times as decoys
The point is that SAs break the transaction graph, making tracing the flow of funds impossible. 1. each SA only appears for a single output 2. it's impossible to know which is the true spend
> it's impossible to know which is the true spend Not impossible. My tool *automatically* detects the true spend 1 in 15 times. Better tools (like ciphertrace's) do better. Lightning is superior.
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