Cryptocurrency and privacy don’t fit together as easily as you might expect. Blockchains give you the illusion of privacy via pseudonymization: you don’t put your name on a blockchain, but you do put information on a blockchain that can be used to determine your name. Blockchain analysis can often reveal information that no one intended to share.
This is true even for privacy coins like Monero and Zcash. These coins put less information directly on chain in the clear, but they still have to be used with skill to maintain privacy. And because they can offer more privacy, they are harder to use. For example, an exchange might let you swap between a thousand different currencies, but privacy coins are conspicuously missing from the list of options. Or maybe you can move money into Zcash, but not with privacy, i.e. not into the shielded pool.
The Privacy trends for 2026 report from a16z summarizes the current situation very well.
Thanks to bridging protocols, it’s trivial to move from one chain to another as long as everything is public. But, as soon as you make things private, that is no longer true: Bridging tokens is easy, bridging secrets is hard. There is always a risk when moving in or out of a private zone that people who are watching the chain, mempool, or network traffic could figure out who you are. Crossing the boundary between a private chain and a public one—or even between two private chains—leaks all kinds of metadata like transaction timing and size correlations that makes it easier to track someone.
As is often the case, the weak link is the metadata, not the data per se.