Are public addresses from the same private key related in a way that governments can trace?

Apologies if this is a dumb question, but I'm having a hard time finding [or perhaps understanding] an answer in my research into PKC.

As the title says, I'm wondering if in a scenario where my government decides to 'go after' bitcoin holders and either try to seize or unfairly tax them, if they knew one of my public addresses, would they be able to [with reasonable effort] figure out the total holdings of the private wallet, or figure out any of [all?] the other public addresses that wallet has generated and used?

Context: the exchange I've been using [Shakepay] is apparently getting more pressure from the govt to reduce privacy and is straight up saying "the govt is making us ask, what kind of wallet are you sending this bitcoin to?".

I'm planning on checking out Bull Bitcoin and moving my purchases over there going forward if I like them, as I've heard they are the best for non-KYC for Canadians, and continuing to use newly generated public addresses every time I send a sizeable amount to my hardware wallet.

Any thoughts and opinions are welcome!