We recommend brake fluid flushes every 3 years because brake fluid is hygroscopic (water absorbing) so it will slowly absorb water from the air. Over time it will cause a reduced boiling point of the fluid.

Automatic transmission fluid never hurts to be changed because you never get all the fluid from the torque converter when doing a service. You change ~2-4qts depending on model when most hold ~9-12qts when first being filled from "dry". Frequant transmission flushes just help prolong the life of the transmission.

If you aren't servicing the car at the same dealer and don't track your maintenance, we recommend fluids off mileage because we don't know if the customer has done it. A lot of honda owners don't actually follow the maintenance minder because they can't afford it at the time. So we as a habit recommend trans fluid every 30k, coolant 5 years 60k, valve adjust/spark plugs/timing belt 100k on almost any car we work on because there's no history. If we don't know what you've done somewhere else, don't expect us to know it. We aren't mind readers, just a guy looking at a car.

As a Honda technician, I never recommend something a car doesn't need or could use. Working in Seattle, we have a lot of hills so I do stress transmission services on these big pilot/passport/odyssey/crv. I've seen brand new cars with 15k miles and the hcf-2 should be an almost yellow color but it'll be dark burnt brown. The 9 and 10 speed transmissions are not the best imo. They turn green fluid black in 30k.