[Norski]

This came to mind, yes.

Also understand that a ransom paid in bitcoin to business hackers recently was recovered by a governmental agency. - Colonial Pipeline, possibly?

Wondering how that was accomplished. Should it not be impossible with cryptocurrency?

[Rurudyne]

Since people can maintain a copy of the key then possession of the Bitcoin is itself dependent on the history of its transaction.

Oddly these crypto currencies are very much like the giant coins of Yap, whose current ownership is entirely dependent on each coin’s oral history of ownership. It should be further noted that even stone coins lost to the sea in transport from where they were made their value is still maintained since the oral history for each is able to be maintained. In general none of the coins is physically moved anyway once in place.

[Database]

Also understand that a ransom paid in bitcoin to business hackers recently was recovered by a governmental agency. - Colonial Pipeline, possibly?

Wondering how that was accomplished. Should it not be impossible with cryptocurrency?

In order to maintain control of bitcoin you need to maintain exclusive control of a cryptographic key, the private key. This key allows you to digitally sign a transaction to move the bitcoin. So, to recover the ransom, they needed to acquire this key or find someone with access to the key willing to help.

I understand that the FBI seized the hacker's web site. Maybe the site stored the private keys. Or they may have traced the bitcoin payment being sent to an exchange to be traded for fiat currency so the exchange had control of the bitcoin.