The UG compax "Nina Rindt" was basically just waiting for this rise, as it's a rare watch with both a (tangential) motorsports/celebrity pedigree AND a clear, undeniable photo of one on the wrist of the celebrity in question. No magnifying glass needed on a grainy photo of half a bezel and pushers under the cuff of a firesuit; this one's right out there in the open.
Secondarily, I don't think it's a conspiracy so much as old-fashioned taste-making - the guys at Hodinkee are seen as authorities on good taste in vintage watches, and so the crowd tends to follow. There are tons of watches they feature that don't go shooting up in value for every one that does.