Dangerous to use if you're not careful. I guess that is one of the many downfalls of not having secure defaults. Taproot and Schnorr are slowly coming to bitcoin. But would this blog post even exist if they had used a coinjoin/payjoin or lightning?
It seems like the kernel of Bitcoin is maximally open information, not secrecy. Obfuscation of transaction is possible, but any solution that could actually hide transaction information would be incompatible with the trust model that Bitcoin is based on.
In fact the US government put out a bounty to trace monero transactions just after Ciphertrace made such claim, and ciphertrace failed to win the bounty, so it appears to be ineffective