Nothing shows up eating more than 4% CPU. Also when I go to sleep with battery at 100%, turn off the WiFi for the night and close the lid, I often find battery

Nothing shows up eating more than 4% CPU. Also when I go to sleep with battery at 100%, turn off the WiFi for the night and close the lid, I often find battery at around 30% the next morning. Don't tell me it's a user problem. I suspect 128GB RAM is eating too much power or something. I also refuse to visit Apple "geniuses" as they don't honor appointment times (fed up from waiting 2 hours until somebody talked to me) and then going through 30 minutes of trivial questions before they actually do something. Not mentioning they always wipe out drives when they "fix" something and I end up with some refurb motherboard that failed for somebody else before.