Coinjoin transactions are actually effective because they give you total privacy without revealing your transaction data to anyone.
They do provide privacy, but not as much as with the methods that involve absence of transaction connection. ChipMixer was giving you chips that were generated before you deposit, and contained no connection with your deposit. That was better than with coinjoin.
You are lying. You forfeit your privacy every time you deposit and withdraw to the mixing honeypot. This is the opposite of coinjoins, which never forfeits your privacy.