Well, the term „emoji“ does not come from „emotion“ at all („emoticon“ does). „Emoji“ (絵文字) is literally a „picture letter“.
Some of them do express emotions, of course. I would agree that I don‘t need something like 🥳 in my push notifications, but for example 💳 or 🌈 are just depictions of things and don‘t carry any certain emotion in my opinion.
So, I personally think using emoji as a substitute for small icons is fine. Of course it depends on how they are used.
