This is either the boringest five-star book or the most interesting book there ever was on forks and farting, probably both.
Elias, who was writing in the middle of the previous fascist wave, right before it started getting extra-deadly - his parents would die in concentration camps - was interested in something less timely, the history of things like table manners, over the longue duree. He collated a ton of etiquette manuals from the fifteenth to nineteenth centuries and found them getting stricter and stricter over time, both in terms of what they directly enjoined and in what they assumed their readers would already know. Boundaries between bodies, taboos against the acknowledgment of them, norms of banishment of hostility, all get removed. He calls this the "civilizing process," with a preface qualifying that in Germany Zivilization implies something rather superficial, like table manners (but also more serious things like extramarital relations and open carrying of weaponry.)
His theory behind this is elaborated in the second book (which hopefully I'll read soon!), but from Vol. 1 it's clear that this is driven by a two-level causal account. The proximate cause is class signaling, wanting to appear higher in rank, or at least no lower in rank, than one actually is - and while everyone who reads this thread is likely to know one can make accusations of signaling rather promiscuously, Elias demonstrates pretty well that he's not accusing anyone of hidden motives but that this is the explicit motive, often the only one, appealed to in the primary sources themselves. "Don't do this or you'll come off as some sort of peasant/poor/provincial," they say again and again.
The longer-term causal force is that the ruling classes themselves - the people everyone wants to imitate - are being placed more and more under external social control, as the feudal nobility start becoming court aristocracy accountable to the crown, and those in turn replaced by bourgeois responsible before the market. (Elias doesn't talk about the disciplining effects enacted in people initially resistant to becoming wage laborers, but it's certainly something that slots in well.) The habits of discipline are internalized, both within the person and within the newly created "private sphere" of the individual household, where bodily functions and moral education are increasingly confined. Westerners of Elias' day are prone to see non-Westerners are "childlike," because, like Western children, they haven't internalized the incredibly historically specific and weird sets of habits that Western adults have (though of course the reverse also applies to some extent, since every culture has their own taboos - though Western ones have gotten much stricter in the course of a few centuries.)
It might be because I'm fresh after reading Angela Nagle's "Kill All Normies," but all of this seems more relevant to the online culture wars than it should be. Nagle makes many references to conscious counter-movements against this process, antinomians from Sade and Nietzsche through the Decadents and Hippies; Elias also acknowledged that there are rumblings along this process as well as periods where the tide ebbs - though neither really theorizes much about why these appear when they do. (Elias is keen to note that an apparent relaxation can be the consequence of actual, or at least otherwise, strictening - women being able to wear more revealing clothing, for instance, having a precondition men being less likely to sexually harass any women willing to bear an ankle, for instance.)
In the contemporary moment I'm inclined to say that what *might* be driving some of the culture wars is a polarization of the degree of social control, resulting in turn from a stregthening in the relative power of capital over labor. On one hand, those in precarious employment, especially but certainly not exclusively in the humanities, are subjected to extremely intense social control, which cannot help but become internalized; this involves a lot of signaling of middle class status and adherence to the kinds of norms that are functional in a highly cosmopolitan society. On the other hand, you have a lot of young men who go straight to being "raised on the Internet" to NEETS (though also in some cases moving on to more stable employment), who have this reflexive and loudly proclaimed aversion to "signaling" and really self-control in general as inauthentic. I'm not an expert on the subject but you certainly see this kind of labor force dualism used to explain the appeal of Salafism and so on to young male losers who happen to belong to a different demographic category than the one WNs recruit from. And this also explains the specific nature of a lot of WN/Salafist complaints: social atomization is real but unevenly distributed, and they're dealing with a lot of it.
I haven't thought all this through too deeply, though, which perhaps just means I should shut up and get to the next volume.