In the past I'd say performance, but at least with your sequential benchmarks, your performance seems fine with that encrypted drive.I don’t really need the encryption, so I can get rid of it if it causes issues. Let me know what the negatives are. Thanks.
I personally don't like encryption when it's not necessary because it needlessly complexifies things. If in the future you say transport it to another machine but don't remember the password, then you're permanently locked out of your data. And if you ever need data recovery for a failed drive, it's basically impossible, although you should ideally have multiple proper backups so you wouldn't need data recovery.