http://whirtorrgetftvz4g466sjqkegtyi35bjl4bvotfkfossunf5my4x6ad.onion/blog/is-bitcoin-anonymous
What this means is that if any exchange, service, or platform that offers any cryptocurrency services asks for the identification in the form of a passport, ID, or even a bank statement, it can connect the real-world identity with the cryptocurrency wallet. If that happens, every single transaction that occurs from or to that address or the available wallet is then connected to the owner’s identity.