Just to add a counterpoint, I handle a lot of customer service and the service provider I use happens to have this feature by default, and it drastically helps

Just to add a counterpoint, I handle a lot of customer service and the service provider I use happens to have this feature by default, and it drastically helps me to respond faster to customers. To date I haven't had anyone consider this an issue (even when I've accidentally sent a response before they even sent their message! - they just end up deleting their text and saying "thank you")