How did you know it was a non-service wallet you encountered before?
Another thing is, sometimes it is difficult to identify some wallets that are owned by some entity, because what if they are using multiple wallets and separating the funds for particular reasons or fields that where the funds will use?
Because that transaction had one input and 2 outputs - my address and change. Services usually do batched withdrawals when they pay to many addresses at the same time, and they also use many small inputs in their transactions, which are the coins that were deposited by users. A single or a few large inputs happen when their hot wallet is empty and they use funds from the cold, or freshly refilled their hot wallet from the cold wallet, or if they had just consolidated all their UTXO. I find it extremely unlikely that when I received that payment, it was a service that had to process just one withdrawal and they only had a single 400 BTC coin and no smaller input.