This was an edge case and only kind of helped because the user connected to a Chainalysis Monero node and swapped on centralized exchanges. No crypto can keep you private if you do those things not even Monero.

Even then if you watched the video notice he says:

"might be the user",

"no strong indications"

"I don't feel confident"

"we have to keep in mind that's just one possibility...we do not know with any certainty..."

"not many bread crumbs to follow"

They're basically just grasping. It wasn't actually deterministically traced just *possible* leads