Attaching pictures, being able to review the content for accuracy/completeness before sending it, being able to pause and do something else in the middle, B/CCing others, and having a copy of the sent document for the record are all pretty helpful. The reason I'd forgo those benefits and call is if I thought I was going to be able to talk to a human right now and just get it done without a to-and-fro.
For example, calling 0800-TEXT-HN and narrating this comment back-and-forth to an machine would be pretty nutty.
That's true, but isn't it so awkward to type, or maybe you're disabled so it's difficult or impossible.
So you use a voice memo to capture your words and email them, but it seems almost as silly as calling up and chatting to an LLM, which has the added benefit of being able to confirm it has understood your request and maybe even begin actioning it.
However, this is silly talk, the real future is just gonna be your agent who you talk to directly, who then talks to the contractors' agent, who passes the info on to them in the exact format they like.
For example, calling 0800-TEXT-HN and narrating this comment back-and-forth to an machine would be pretty nutty.