I googled and read some Coinbase docs but didn’t see a definitive answer. If someone sends btc from their Coinbase exchange wallet will you be able to see the rest of their activity and where their btc went? It seems the answer is no since it sends from a different wallet every time, though I am iffy on this.
Also, for the record, I know this is bad practice and don’t recommend anyone keep a significant amount of btc on website-based wallets.
Note that I am not concerned with whether or not the BTC that is purchased is associated with a person’s identity, or whether the exchange itself can see all of your BTC activity. Just asking if anyone exploring the ledger could see all of your activity grouped together.