I agree. At the same time marketing for the PRC's was/is getting match grade performance right over the counter.
Some of the things I've read on 24hr was that some ammo was loaded properly (close to advertised velocity) and other batches not so much.
It's odd when manufacturers do that. Sometimes you have some cartridges loaded so well that its hard to match factory velocity(338 Federal/ 325 wsm come to mind). Then you have old cartridges under loaded due to older rifles being around. I don't see reason for PRC's to be under loaded/not as advertised when you have modern rifles for the specific modern cartridge.
Could just be differences in guns too. Some are slower, some are faster. If Hornady is using a fast gun for their numbers and your gun is on the slow side then 200fps difference is not out of the question.