I really wish they didn’t allow altcoins on this forum at all. There is nothing that can be done using any altcoin that can’t be done with bitcoin. You can make bitcoin private, you can make bitcoin faster, bla, bla.
Satoshi actually talked about making bitcoin private here:
https://bitcointalk.org/index.php?topic=7.0Altcoins have given bitcoin more value. Bitcoin is the value store used for trading in altcoins. More altcoins are traded against BTC value than against fiat or any other value store.
While for illegal use bitcoin has its downside - for genuine uses the pseudo anonymity means that there is a clear audit trail.
Bitcoin is still the standard of decentralization.
It is the hardest coin to launch a 51% attack on.
Cost of launching a 51% attack:
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Source:
https://thenextweb.com/hardfork/2018/05/30/heres-how-much-it-costs-to-launch-a-51-attack-on-pow-cryptocurrencies/None of the current privacy coins have yet shown that they can be trusted.
Monero uses Ring Confidential Transactions.
While monero hasn't been exploited - The bytecoin network using the same technology was exploited.
The issues surrounding the MoneroV fork show the vulnerabilities of that technology.
https://serhack.me/articles/introduction-to-monerov-and-its-inherent-risksDash (Darkcoin, xcoin) uses Joincoin
Thanks to masternodes, the probability of tracing a payment is very high.
Zero coin based privacy coins have run into trouble several times with multiple exploits resulting in excessive coins being minted.
Zcash - if there was an exploit it is likely that no-one would know.
Source:
https://zcoin.io/zcoin-and-zcash/Verge (Dogecoindark) - several recent exploits.
So privacy features that those coins provide over bitcoin are just a comfy blanket. Whether they actually work still has to be seen.
It could turn out safer to put your bitcoin through a mixer.