A sage and wisened engineer once shared that a hydraulic system will last forever if kept clean inside. For the Pilot, that means that the power steering fluid gets replaced regularly. Ours is on a schedule coincident with brake fluid replacement, so every two years max. The brake system is the other major hydraulic system on the car, after the automatic gearbox and the power steering. All deserve very regular fluid change services.
The power steering pump is a rather simple sliding-vane pump with an internal pressure bypass. Little phenolic plastic plates slide on slots in a rotating drum as it spins in a larger casing. Those plates/vanes wear slowly, and shed their dust through the system. It may interfere with the internal bypass valve, and may also interfere with the spool valve in the steering rack. Either will cause the loss of assist reported, especially at low engine speeds. A full flush of the steering system should include actually running the engine with a fluid supply and a catch can plumbed in where the existing reservoir sits. But just a regular turkey-baster removal of the reservoir fluid and replacement with new will help a lot, and is simple and not nearly as messy. If you already have the symptom though, a full flush and replace may be in the cards for you. For sure it's a way cheaper thing to try before replacing the rack itself.
For those playing along at home, change those fluids regularly!
