[hokiefyd]

Without knowing more, I'd guess there's a contact point there where that plastic panel with the license plate lights rubs the paint over time. Pretty unfortunate for sure, and maybe something that someone with a newer Pilot that isn't yet rusting can avoid with some helicopter tape or something like that.

 

[hokiefyd]

I inspected our 2022 recently and found no rust there, but I didn't expect to find any. We do live where they salt the roads in the winter, but it's not a heavy duty cycle, and we don't drive our Pilot when the roads are salted (wait for them to dry).

When I was looking at ours, it looks pretty apparent to me that this is a case of that lift gate garnish rubbing on the paint in the license plate area, rubbing through the paint, and then that area starts to rust when you get a bunch of salty spray kicked up and sucked into that area from the back draft as you drive forward.

Though I don't know how difficult it would be to do, I think a relatively low-effort migitation for this, especially for those for whom the rust hasn't yet started, would be to remove that lift gate garnish and cut and install some adhesive clear plastic film behind the garnish where it'd rub the paint. Some call this film "helicopter tape" and many cyclists use it for a very similar purpose: to prevent cable housings from rubbing paint off the bike frame. This should keep the garnish from rubbing through the paint there (and might even protect paint that's rubbed through but not yet started to rust).

I just don't know how easy it'd be to get that garnish off. I presume it'd involve removal of the interior lift gate panels to get at fasteners from the inside. If the fasteners are accessible from below the garnish, from the outside, then it should be pretty easy.