Sit next to someone answering a routine support email and time each part. The typing is the short bit. Almost nothing goes there.
The clock goes to reconstruction. Figuring out what the customer is really asking. Finding their order or account in another tab. Hunting down what your policy says about this exact situation, or pinging the one person who keeps that rule in their head. Then writing the reply, rereading it, and sanding the edge off, because getting the tone wrong with an already-annoyed customer costs you a refund or a review.
Now add the switching. Every ticket yanks your team off whatever they were doing, and the queue never tells you it is finished. It just refills.