There is reason to mention it (IMHO). When timing belts became commonplace the equivalent question about maintenance might have been "Does my 19## Civic, Accord, etc. have interference valve train?" If one had ever had the sad experience of a broken timing belt resulting in the entire engine having to be replaced one would remember it well. If that same person a few years later had another more advanced Honda they might not even know anything beyond how much it cost them xx years ago to replace the engine. But they would remember that it was due to a faulty or broken timing belt. It strikes me as worthy of mention if for no other reason than to inform owners about their vehicles. I have a high mileage CRV that I "inherited" from my daughter and despite serious searching didn't fine anything about timing chain until this evening. The only other Honda in my family was an '02 Civic Coupe that has since been passed on to the other daughter. She got it from me AFTER I had recently replaced the timing belt. She and countless other driver's probably has little or no idea about the difference between timing chain and timing belt. Automobile manufacturers willfully withholding critical information from their customers do them a real disservice, while at the same time providing their dealerships with lucrative repair jobs.It won't be in the owner's manual because there is absolutely 0 reason for it to be there. The only thing that adding info about the timing chain would do is confuse 90% of buyers who know absolute squat about anything mechanical.
Now if you bought the HELMS maintenance manual or have access to Honda's digital tech data you'll find it right away including step by step on how to change it if you ever had to (you won't unless you ever have to rebuild the motor).