This is why you reply with this: https://nohello.net/en/
It's purely a cultural thing, people from some cultures find it rude to get to the point, so they need to have this "hi, how are you" -preamble every time, even if the other person is on a completely different timezone, which makes every chat take 2 days.
I'm a big proponent of the whole "just start with your question" thing but anytime someone replies to a "hello" with just a link to that page, they immediately come across as a jerk.
Or I'm setting boundaries.
Getting a "hello" from your superior with nothing else is akin to "come to my office first thing tomorrow morning" without extra context.
That day is ruined as well as the next one unless the manager is 5000% explicit that it's a good thing.
If your way of setting boundaries is to reply to a message with a URL, I consider you a jerk.
It's got nothing to do with your boundaries.
I like to put this as my slack status for a while when I join a new job. It tells my coworkers I mean business, and sets healthy communication patterns right out of the gate.