Before, I could think you were simply misinformed. But when you say "I have read plenty about them and it's still possible to track those coins through various means using various pieces of metadata", you're either lying or unable to understand what you've read.
I could give you my Zcash z-address right now, & there's no way known to cryptographic science for you to know its balance, when and how much ZEC it has received or sent, from or to whom, or even if it's ever been used at all.
None of the metadata thrown off gives any hints to that. Even godlike omniscience about my every interaction with the internet, or a man-in-the-middle attack against all my connections to other Zcash nodes always, would only indicate that I have interacted with the network, and likely sent transactions at cerain times. You'd still know nothing about my address's activities. (The case is somewhat weaker for Monero, though savvy Monero users can start to approach Zcash's privacy with some extra steps like 'churning'.)
If you keep spreading falsehoods, you're harming people who have a right to know what's technically possible, whether they like the implications or not.
And while I'm unlikely to convince you, any other lurkers who want to do their own research, and confirm my claims, should take note: I am providing truthful, reliable info here, under my real name, which you can use to discover many other facts against which to calibrate my credibility (including the fact that I'm a compensated advisor to Electric Coin Company, the original developers of the Zcash software). A anonymous account is spreading falsehoods that will mislead you. Proceed accordingly.