Angry Couch Potatoes
I saw that list and that's immediately the first thing that came to mind. They all eat a lot of potatoes.
Potatoes are really, really bland. They're not even technically a vegetable, they're just a starch. Filler. Something our obese populations don't really need right now.
It takes so much to make potatoes tasty - spices, cheese, meat, whatever you can add to make them better. At the very least butter and salt.
I used to joke that the reason the English were such colonizing bastards is because their food tastes so awful they raided the rest of the world for better flavors. I only feel marginally bad for making that joke. Partly because I'm only half joking when I say it.
Also their language is gruff. When English speakers say "Pardon my French" the words they're about to use are actually more often than not of Germanic origin. They're dropping their fluffy, Latin roots for some potato-dirt verbage.
I could add beer to this mix, but so many civilizations rely on beer and other fermented beverages that it doesn't seem very discerning to bring it up. Plus you didn't include Belgium on this list, and as far as I've read everyone in the northern Germanic areas took their best beer-making tips from them (that statement may start a fight now - have at it, I prefer vodka anyway).
There's also the fact that their descendants remain oddly dairy dependant, when in reality the majority of humanity should be lactose intolerant - you don't need milk after you're done breastfeeding for most mammals. Yet while roughly 65% of the world's population is naturally lactose intolerant, only roughly 25% of these Germanic populations are. Although if you're wondering that does not mean the rest of the world doesn't have a rich history of dairy production; unfortunately it does mean that you need to ignore these people if they try to tell you how to do dairy, because they don't need the microbes you do to break down lactic acid.
(fun link: https://www.discovermagazine.com/planet-earth/what-mongolias-dairy-farmers-have-to-teach-us-about-the-hidden-history-of )
If we're hoping to find some sort of common, gosh-this-racial-group-just-produced-some-right-bastards genetic or cultural underpin that explains what the hell is wrong with them (actually I should say us as I'm a mutt of this genetic variant myself), I've got nada.
Unless maybe just centuries of stuffing yourself with starch, alcohol, and lactic acid makes for creating a cultural group of angry couch potatoes?
Hmm, yup gonna go with that.
*post title set*
A huge ethnic group?
The Germanic languages (ethnic group) are related in the sense that they can be shown to be different historical developments of a single earlier parent language. Although for some language families there are written records of the parent language (e.g., for the Romance languages, which are variant developments of Latin), in the case of Germanic no written records of the parent language exist. Much of its structure, however, can be deduced by the comparative method of reconstruction (a reconstructed language is called a protolanguage; reconstructed forms are marked with an asterisk). For example, a comparison of Runic -gastiz, Gothic gasts, Old Norse gestr, Old English giest, Old Frisian iest, and Old Saxon and Old High German gast ‘guest’ leads to the reconstruction of Proto-Germanic *ǥastiz. Similarly, a comparison of Runic horna, Gothic haurn, and Old Norse, Old English, Old Frisian, Old Saxon, and Old High German horn ‘horn’ leads scholars to reconstruct the Proto-Germanic form *hornan.
Germanic languages, branch of the Indo-European language family. Scholars often divide the Germanic languages into three groups: West Germanic, including English, German, and Netherlandic (Dutch); North Germanic, including Danish, Swedish, Icelandic, Norwegian, and Faroese; and East Germanic, now extinct, comprising only Gothic and the languages of the Vandals, Burgundians, and a few other tribes...
I have my own personal opinion on this topic. I think the representatives of the above-mentioned nations are distant relatives of each other. This is reflected in their languages and cultures, even in their appearance. I want to know exactly what unites this group. So are they really related? What do you think?