Blockchain are very transparent. Only special coin protocol can be done to make tx private: Monero, Beam, Zcash.
However DeFi is a great service but all your financial data is onchain?!!!!
As long as CeFi ones aren't hacked they can be much more private to use which is crazy to think about. BIG OOF
Beam though is working on a private one. IDK if it work but sounds cool:
https://decrypt.co/33217/privacy-coin-beam-wants-to-reinvent-decentralized-finance
If you don't know Beam it uses mimblewimble to provide privacy. Due to that tech the blockchain actually becomes more smaller with more use.....
From what I read from the article, Beam will have a HF which will add:
Will be interesting on how it will work, intersting to note some of these tech are also able to be used on LN(little diff of course....)