It's nothing out of ordinary.
For example, the last batch sold in an auction in 2020:
https://www.usmarshals.gov/assets/2020/febbitcoinauction/
contained coins seized from Alexandre Cazes, in case you don't know who the guy was, we're talking about the founder of Alphabay, who was arrested and then died in jail in Thailand in 2017. So a 3 years waiting period is nothing out of the ordinary. There is a different case listed there that dates from 2016.
If they are going to propose to cut your jail term from 30 years to 10 if you let them size your coins I'm pretty sure your mind is going to tell your mount to start talking seeds and passwords. And this if we talk about governments that still play by the book, if we talk about the ones that have no problem helping their citizens to commit suicide all you encryption will break when your first finger bone snaps.
Look what happened to the guy I've mentioned above, how confident will you still be once you know you're a target?