1. The mixing service you advertise charges more than zkSNACKs does for coinjoining.
For this specific service, I don't know, as I haven't tried it yet. The past two services that I've used, ChipMixer and Whirlwind, charged me nothing.
2. Mixing services are not effective since they do not provide privacy to their users, they collect the data of their users and turn it over to the government.
You don't have the evidence to support that claim for neither ChipMixer, nor for Whirlwind. You just make assumptions.
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 wrong again:
And yet, nobody knows what this 7 TB is all about. As far as we can tell, they got access to chips, but that's all we know.