I'm not particularly sorry, but when I ask questions out of the blue over email or chat, I always explain what I've already tried. The two exceptions are when it's urgent, in which case I briefly explain the urgency ("prod is down did you deploy just now?"), or when it's part of an ongoing conversation.

If this is not typical for you, then you are surrounded by people who disrespect you and your time.

It's not typical but it's how you should personally act.

You aren't going to be able to convince others to be upstanding coworkers that actually give a damn, but you can be that person yourself.