I can't give legal advice, it also depends on where you live. Where I live, after holding btc for a year, it's none of the state's business what I do with it. Under one year, they want taxes on gains when spending. Spending could mean you send from onchain to a (non kyc) wallet provider.
Discussion
I think its a tax free event after one year of holding it. So if i understood you correctly, it wouldn't be the badest idea to make a 'spending' transaction to another hardware wallet after one year of holding it. Then the receiving anonymus part of the transaction has kyc free bitcoins. And from there the anpnymous part can do a coinjoin with parts of the holding and tranfere it to a lightning wallet? 🤔😁 #[4]