Good point. A few things about this:

Casa client data is encrypted by your account manager's personal Yubikey, which means they make a real legitimate effort to limit how many clients any given employee has access to. The govt would require your account manager's cooperation to get your info. Although there are possibly other ways to dox you too, from KYCd corn and chailalysis, or bad privacy practices from people you transact with.

Ultimately, unless you are a kyc-free bisq ninja or whirlpool everything, you don't have deniability anyways.

IMHO it isn't a huge concern unless you already have perfect on-chain privacy. And not many people do.

Also, you can use Casa anonymously, but you lose 2 benefits:

I began using it anonymously, but then decided to reveal my identity because I want my family to be taken care of if something happens to me. That peace of mind is worth more to me than worrying about getting 6102'd.