Ok I guess they don't because you say so. I forgot how important you are
Yeah I'm not important at all... but for you to make such a bold statement without much prior knowledge doesn't make you an expert.
When it comes down to loading up the 919, common sense comes into play. If you mess up the balance between front/rear tires, then of course you're going to notice issues. If you don't compensate, then you'll have issues.
Even before upgrading to the ohlins (Haven't done any long trips yet) and rocking out the 02 stock suspension fully loaded, I haven't had nary an issue. There is the possibility of experience (or lack thereof?) on other bikes when comparing to the 919 (same for vibrations?). For example, my 250 ninja was so nimble, but also under specific conditions, it felt very twitchy, and hitting bumps mid corner at specific angles made the front end come alive in a not so great way. Compared to when I switched over to the 919, I was complaining that the front end had no feel/feedback.
Keep in mind, just about any bike would benefit from a steering damper to some degree. However, to say the 919 NEEDS one such as what you claimed is simply false. I'm sorry.
Now, if you want one for your specific situation, then by all means get one! If it helps you, great! Just don't forget about the basics and if they're not attended to properly, a steering damper will likely just mask over the real issues and that could be dangerous.
Food for thought: I've always noticed (and so did my wife) that the 02-03 rear shock always handled/responded much better than the 04+ rear shocks when riding 2-up. Might be possible that the 02-3 shocks might benefit those who run with full luggage and/or fully loaded up? I could see some issues popping up with 04+ rear shocks with the 919 fully loaded and/or riding 2-up. I never seemed to be able to find a happy medium on the 04+ rear shocks when fully loaded.