Unit 1. Optane memory is useful for people who want very, very fat performance like production tasks. It’s probably better to have an SSD or a hybrid drive. A hybrid drive is a small SSD + large SATA combined which learns what you use most often and preemptively loads it into the SSD.
16GB + i5 is better than 8GB + i7. You might even be able to do alright with an i3 for browsing, streaming and writing.