I've been thinking through how to do this. I agree notifications can be overwhelming, especially when you don't know what the reaction is to. You can click on it to open the note but to have to click on every reaction of potentially hundreds isn't realistic.
Discussion
Something like this. Probably have the username equal size as note text, or maybe have not text actually smaller, as the notables here are the rection, and the usernames. Maybe with a smaller version of the pfp in between?
But no idea how tricky this would be. It's an aggregated view, so it's also tricky to combine this with the view. Timestamp would be last reaction, so a viral thing would keep bubbling up. One way would be to cap it at a fixed number of reactions, and if it overflows, you would get a separate aggregated reaction note.
I've put it on my to-do list to try and figure this out. I'll see what I can come up with.