You can collapse it. It won't go away, but it won't appear as an icon in your tray anymore, and you'll have to do an additional swipe to see it. Very likely what you want.

Long press the notification

Press the gear on the right side

Go to Notification Categories near the bottom

For ntfy, the one you want is “Subscription Service”

Click “Silent” and check “Minimize Notifications”

If you don't see different categories, you may need to turn them on. That's Settings –> Notifications –> Advanced –> Manage notification categories for each app.

Bonus: Once you've got notification categories turned on, you can (on most well-behaved apps) disable marketing/“your friend just liked” notifications but keep the ones you actually want to see.

I'm on a Samsung, the labels might be slightly different for other Android distros.

Minimized notifications are all grouped together and don't show an icon. I silence all of my persistent notifications, including Android Audio and the charging-related ones.

The reason you can't/shouldn't turn it off entirely is this is the official way for an application to constantly stay awake and hold a connection open.