I was just about to make a post about this issue. I've tried adjusting every setting imaginable to get the best out of my battery life without creating a non-basic experience, yet it still drains the hell out of my battery since the update.
I noticed the options in Device Care > Battery, to put your phone into Power Saving, Medium Power Usage, Maximum Power usage, and Optimisation are gone in this update.
I tried to organize apps into Sleeping Apps & Deep Sleeping Apps, yet they're still opening in the background, even after un toggling the ''Allow background data usage'' & ''Allow background activity'' in the usage setting in app info.
Also, all the Samsung bloatware, mainly Bixby and AR apps are still trying to open themselves in the background and succeeding, even after I've disabled them. It's a pity because I was really looking forward to this update.
In short, my battery is draining at an uncomfortable/ noticeable rate and I don't think Samsung got the optimization part of this update aced yet.
Anyone with similar issues?