Before smartphones, it seems to have been the standard for just about every form of instant messaging. Well, morse has no capitalization and telex would typically have been uppercase-only too, but I think we can still count those?
I suspect that this is just something that happens naturally, for shorter-format messaging typing in sentence case probably offers no added readability and tends to get dropped over time.
I suspect that this is just something that happens naturally, for shorter-format messaging typing in sentence case probably offers no added readability and tends to get dropped over time.