A. Drastically reduced anonimity. With a simple filter of transactions anyone with half a brain could identify transactions coming from YoMix.
While their mixer is new, bitcoin transactions are forever. In short notice, mainstream services will see all their transactions and potentially even block you retroactively if you had ever touched coins related to YoMix.
More than one mixing service was seized by law enforcement agencies in both the United States and the European Union. However, no retroactive decisions were made. Some users even deposited Bitcoin obtained from signature campaigns or used those mixers without the account being suspended.
The arguments you cited are weak, and I noticed that since you logged in here you attacked that service, even though you have not published since 2018. Can you sign a message from this address 13sFVaYNrnguJywMQkQB2ypVCwHSH2s7mt
I'm new to this, but here goes a try!

-----BEGIN BITCOIN SIGNED MESSAGE-----
I am Russtie Beerkan from bctalk and it is currently 29/11/2015 12:19 am utc
-----BEGIN BITCOIN SIGNATURE-----
13sFVaYNrnguJywMQkQB2ypVCwHSH2s7mt
H5vTZzFTwhJkj7madIPfUbq7lMbaIzPYriQvwgPxZM9CSk7s3dI2cPJQuPhQbUiKlmq56Im1DUw32y3l4y6ezZ0=
-----END BITCOIN SIGNATURE-----
How to verify? Thahks!