I get the sense you understand what I am trying to say.
But I still dont understand what you are trying to say.
So far, your examples seem to parallel features of Forgotten Realms.
Maybe explain what makes Birthright ‘feel’ different from Forgotten Realms?
Okay in detail.
- The world is made up of kingdoms ruled for the most part by monarchies. Sole rulers that form a kind of club of regents or an elite amongst elites. Vs the forgotten Realms being made up of a mix of everytype of system and plenty of areas with no system of government at all.
- The kingdoms are all vying for a finite amount of power in competition for shared resources with each other and for the most part in highly developed kingdoms. Vs forgotten Realms settlements largely being surrounded by wilderness and not in competition with each other (sword coast, silver marches, dalelands etc)
- Birthright is largely ethnocentric, races do not mix easily and dwarves keep with dwarves, elves with elves etc. there are some exceptions but they are rare. Humans are divided in ethnic groups that are geographically bound. Vs forgotten Realms where almost every settlement is a mix.
- The elven race was at war with the human race for hundreds of years and this defines both their division in the world and their various specialisation (elves have no gods, normal humans can’t cast arcane magic above lvl 2). These races are still at odds and interaction is rare. Vs forgotten Realms where there are no major race divides.
- Society in Birthright is made up of blooded individuals which form an elite which covers the entire continent. Blooded characters are fundamentally different in so much as only they have the right to rule. Vs forgotten Realms where there is no unified elite sharing a single characteristic.
- The setting is low magic. Blooded Wizards able to use true magic are very rare vs Forgotten Realms where every other innkeeper is an archmage (read Volos Guide to the North)
- The setting is low power. Most regents are levels 3-7 with a few exceptions vs Forgotten Realms where every other blacksmith is a retired adventurer.
- There are a small number of extremely powerful monsters - the Awnsheighlien which can rule their own kingdoms as regents do. There is no analogy to this in the forgotten Realms that I’m aware of.
- Alongside the war between elves and men there is a parallel conflict between the natural world and civilization. This effects the strength of magic in the area and is tied up with the fairytale like nature of fey creatures, unicorns, sprites etc. vs Realms where magic is totally independent of the land and this conflict isn’t relevant.
- Anuire which occupies the main, most detailed part of the setting, represents a single empire fractured under a single throne. The individual kingdoms seek to regain that power vs Forgotten Realms where individual lands weren’t united and where they were there is no drive to unite once again.
- Birthright is largely feudal and Arthurian in feel and tone. It also draws on real world tropes and mythology with scandinavian, Germanic, Rus and Arabic themed cultures Vs the forgotten Realms distinctly renaissance, high fantasy, progressive feel.
These are just some of the main differences I say. As I said I am fan of both and have been for many years. Saying the settings are analogous is just plain wrong though. No doubt you could amend the existing Forgotten Realms canon to create something, like what I have described above. However if you did that it would be out of keeping with the existing 5e products and previous incarnations of the Realms. It would cease to be the forgotten realms.