It is just too expensive for the Ethereum network and not a large enough mixing set (haven't looked recently though) and nobody accepts it therefore requiring you to exit it if you want anything, but exiting will reveal who you are because there is nobody else it could be.

Privacy on the Ethereum network remains just Ether in Tornado Cash.

edit: oh cool Aztec actually transitioned to the Optimistic Rollup. That is different than their prior smart contract and requires new analysis. I recall their article last year or before about doing a "zk zk rollup" and I didn't keep following.