I found the setting I think u mean... in Server side settings.
Yes, enabling that, now there is a filter bar at the top of On Now, and, from personal section, pressing back does exit the section. However, I do not want that filter bar on, I do not need it.
The normal On Now, when added to the navigation sidebar, with no Collection Filter on, works fine, u can exit it by going to the nav sidebar. But when you open it from Personal Collections and have no Collections Filter enabled, you are stuck. I have always had Channel Collection filters off. On Now is the only section that does this.