“This is the story of the revelation in late 2013 that Bitcoin was, in fact, the opposite of untraceable—that its blockchain would actually allow researchers, tech companies, and law enforcement to trace and identify users with even more transparency than the existing financial system.”
Oh, I see what you mean now. I have heard of privacy projects that are anonymous sometimes and not anonymous at other times like Zcash and was under the impression that is kind of what you meant.
Those sorts of things exist on Ethereum too. There are also “mixers”, like Tornado Cash, that can anonymize a particular transaction using a normally non-anonymized token. The Ethereum philosophy is to provide a broad range of tools that can interoperate with each other, allowing people to use whichever ones suit their specific need.