It's something the Cypherpunk have been fighting for decades. (There is a good text to read 'the cypherpunk manifesto'). And when people started to think about creating a decentralized currency, well before Satoshi and Bitcoin, they had privacy in mind.
Edward Snowden
Do not take me as a fool only because I think differently from you. Cyberpunks were not criminals, and Bitcoin was born to be anonymous not to facilitate crime and criminals.
It is no coincidence that Satoshi was not happy with the associated Assange and Bitcoin.
Privacy is a right, but it is a must to fight criminals, and I see no use in mixing services, none.
If you want to donate to Snowden what does it prohibit you to Exchange BTC for an anonymous one and then send it for a donation? Explain to me why I should use a mixing if I can use crypto anonymous.
BTC that pass through mixing cannot go into Exchange because they would be immediately blocked, this is the harsh truth and is why they are willing to pay up to 5% tax.