That's part of the story. Certainly, the French have a refined service culture, and, implicit in your cultural/political/class observations is that a modicum of politesse will greatly help your cause.
The Dutch not only have a unique culture, they uniquely have a mythology about their culture that they propagate and seem to believe. This includes:

• Dutch people are direct, not rude
• Dutch teams work on consensus, not hierarchy
• Dutch people are frugal, not cheap

But, as I've observed them, they are rarely "direct" to someone who is their social/business superior, but rather to those beneath them; they'll have a consensus to tolerate clearly ineffective, if not pointless, initiatives imposed upon them from above; and nobody visiting the "crown" lounges would dispute that the catering and upkeep were cheap, and let's not mention the Wanders Boxes. In other words, the story they tell themselves and others doesn't match the reality I've encountered, but, like all good myths, there is some basis in reality.
Dutch culture is also one where people like to avoid the personal touch. They still have automats there! (https://en.m.wikipedia.org/wiki/Automat)
​​​​​The Dutch social world has evolved since the period of "pillarization" (into the 1970s), where schools, social contacts, even insurance companies were determined by whether one was Catholic, Protestant, or communist. Now they claim to be the most secular country in the world (much to the bemusement of Uruguayans, who rightly object that December 25 in their culture is officially and generally referred to as "The Beach Holiday", and not some Christian name like "Kerst"), and they tend to have three social groups: family, work, and gym/hobby.
Of course, every culture has its strengths and weaknesses. Get on their wavelength, and the Dutch can be friendly, funny, a little crazy, and caring.
So, how would this translate to how KLM treats Ultis? Well, you do know that this is a company where the King only rates a short haul First Officer? You are a passenger, not a member of their work social group. You are also paying for a certain ticket, and the fact that you buy more of them doesn't increase the margin on each ticket, so you're not worth any gesture with financial value. This is generally the case with status; it works best when the arrangement helps both sides. Priority boarding? Those who don't fly much don't spend much of their lives waiting in lines. They also tend to spend longer blocking the aisle getting into place. So sending the frequent flyers in first makes sense. Sending the ultis on board before the FAs have determined the cabin is ready? Well, that's work, and, to be direct, you haven't paid for that.

Next up: understanding German jokes: a primer
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