Oh, but I own a 2009 Honda Pilot too.
It is hard to determine which one has bigger junk of brakes, the Sienna or the Pilot.
Sienna, absolutely aftermarket brakes. EBC, HAWK rotors. Not sure about Powerstop. Brembo clearly indicates that their line of rotors for Japanese vehicles and some Euro vehicles is not high carbon.
This is what also happened to me on VW Atlas. Same issue as on Sienna. Which is strange as Euro vehicles usually come with oversized, well cooled brakes. Size was there (335x30mm). I got car with 15,000k. Brand new rotors and pads. Some 5k down the road (something like that) same issue like on Sienna. Get new rotors, new pads, all OE VW at the dealership. 8k later, again same issue. Rotors are made by Brembo. It is engraved onto rotors. So, thinking it is rotor, I get ATE (which I always prefer over anything else). Whne I got ATE rotors, one thing was clear: they are MUCH darker. Cleraly, more carbon is in those rotors. I put ATE at maybe 28k, sold car with 50,000, no any indication of warping. I even kept old pads I got after I had warping for the first time around 20,000 miles.
Now, I must say, I do drive all cars to their capabilities, and many people will not push Sienna through 2-4th gear to redline uphill here in CO.