I've been going through stages of grief with this feature and I don't believe I can reach acceptance. I keep thinking I'll get used to it, but instead I'm missing important messages and, given my reliance on digital organization, it's objectively made my life worse. I just want this: to ungroup notifications by default for the apps I consider critical.
For example, I'm fine to group my excessive and unimportant Facebook app notifications. But if yesterday I received a useful text reminding me of an appointment (and I want to keep that visible) then a new time-sensitive text I receive this morning from my client should not be quietly hidden behind it. There are real consequences and I can't tell my client that "it's Samsung's fault" that I didn't notice.
Because this thread seems very underdeveloped and I feel inspired, here are some observations, in no particular order, that I hope will help with urgency, context and maybe offer some simple ideas:
1. What's it like? As though the post office only shows you one piece of mail, the oldest one you haven't processed, no matter it's a bill or a flyer. Or try this metaphor: it's got the inconvenience of a refrigerator that consists of one drawer with just a single item at the front.
2. The purpose of notifications is convenience, not jumping through hoops. I want the ability to see them all and swipe the unimportant ones manually, period, and I'm done trying to give it a chance. I'm sure.
3. Notistar is a different experience, it's literally a different UI and not accessible through the swipe-down.
4. I get that reducing clutter is a priority. I actually want that too, but this goes too far.
5. If you're going to group them, at least put the most recent unseen message at the front, AND make it much more visible that there exists a stack hiding behind, AND make it more obvious that there are new notifications since I last expanded it. But really, if I have to ask for that many non-trivial changes, then it's just an ineffective design.
6. You know what's even easier? Just let me ungroup notifications by default. Bonus if it's on a per-app basis. Even more bonus if I can easily make that determination and change it on the fly, as I'm using the notifications drawer. But I'll settle for the easiest, bonus-less version in a future minor update.
Thanks, whoever read this far. I appreciate you. 
