Bitcoin was meant to be decentralized and there was no mention of privacy of hiding one's transactions in original code of Bitcoin.
For the record: privacy was mentioned in Satoshi Nagamoto's bitcoin.pdf:
10. Privacy
The traditional banking model achieves a level of privacy by limiting access to information to the
parties involved and the trusted third party. The necessity to announce all transactions publicly
precludes this method, but privacy can still be maintained by breaking the flow of information in
another place: by keeping public keys anonymous. The public can see that someone is sending
an amount to someone else, but without information linking the transaction to anyone. This is
similar to the level of information released by stock exchanges, where the time and size of
individual trades, the "tape", is made public, but without telling who the parties were.
This has since then been called "pseudonymous".
On the mixer ban, I'm cocksure there's going to be a ripple effect that will empower other competitors that can wrestle traffic from this forum.
I already saw a coinjoin campaign that will soon resume.
Already, I've read about a manager who has concluded plans to move a mixing service they're managing here to a sister forum.
Obviously, banning mixers from being advertised here doesn't stop them from being advertised elsewhere. But that's not Bitcointalk's (or theymos') problem anymore.