Sysadmin

Make a list of your priorities, do them in order, what doesn't get done doesn't get done don't worry about it. That's why you have a priority list. As long as you communicate to stakeholders and get agreement on the priority order, then nobody has room to argue.

Schedule a block of time per day where you can't be interrupted so you can get your hyperfocus in. Don't eat into your personal time for this focus time.

What's important is not always urgent, and what's urgent is not always important.

Answering the phone is urgent, it's ringing right now, but when you answer it it's a telemarketer - it's not important. A lot of life is like this.

Without context, to me it seems like you need a new colleague hired who can take some of the random work off your shoulders. This way you can be present in the oh so important meetings and focus on developing the infra.

Let me pinshit about "adhoc", a latin word which most people think of as meaning something like "spontaneous". That's wrong! Ad (to) hoc (this) means "in this regard". If someone asks you a specific question, you could answer "adhoc i have no idea" or "i don't know anything adhoc". There's no such thing as "adhoc work".

I guess, a very important skill is to say no. It's ok to be unavailable to finish a task.
A meeting without an agenda, from my experience, lacks focus and consequently often results. Sometimes asynchronous communication is enough... Personally, i try to concentrate meetings to specific days of the week, so that i have two, three days a week without major interruptions.

Regarding operations, i like to cite: "unplanned work is death to all other types of work, such as planned, or projects"
We do have an operation center, which routes events, incidents, information coming from all types of ingress(events, email, calls, incident tickets) to specific support groups.
Support groups, as does mine, have a so called "dispatcher" role. Someone's main task for the week is to acknowledge incoming events, and to try to solve most (small) tasks themselves - to keep everyone's back free; to concentrate unplanned work of the whole group.