All my emails are on a one hour tape delay, to account for global lunch breaks in time zones around the world.
Somewhere in time and space, people are trying eat lunch right now.
Even SMS gets a tape delay for the first response. What if my phone was on vibrate in my coat pocket, hanging in the closet? After that first response, you'll know I have it in hand, so I'll make with the snappy replies, since I trusted you with my phone number to begin with.
Chats? The window was minimized. What do you want from me? Blood?
Emails may or may not enjoy 24 hour response times. I don't check all of my email addresses on a daily basis. Work emails are starkly divided from personal emails, for legal reasons regarding domain names (DNS) and bare metal server locations and territorial jurisdiction. Some animals are more equal than others.