To offer my own two cents on the Restricted/Limited concepts as someone who does play here:
I think it is disingenuous to compare a low-magic fantasy game to somewhere like Marvel. The focus of the game is on dynastic politics, and in a sense we're kind of unique in that way: it's not like people have to play the servants, the blacksmiths, etc. - in fact they're usually dissuaded! Most people are the 1% of Westeros, so to speak.
So, in this sense, it becomes a little contrived looking if not just the women of Bear Island (a sort of unique culture in canon) can fight, as well as the daughter of Lord Tarth, an important vassal of House Baratheon -- but if the daughters of Lord Arryn, Lord Tyrell, Lord Lannister, and so forth are all on par with great knights, it does begin to break the theme.
But it's not like most of the population are nobodies. Game policy really is to treat Tier IV, the tier of most players, as "good," and above the general cut of the population. Sansa Stark would be an IV - you can play a daughter of a great lord completely without restrictions; and in fact I did play a daughter of Lord Tyrell with no experience at all as my first character. IVs have driven RP and been really influential at court, too, though it does make sense in my mind to limit roles like the Small Council and the Great Lords of the Seven Kingdoms, like we do.
I'm basically someone who really enjoys canon compliancy. Maybe I'm in the minority, but I'm more to ask "what's the point" if I'm playing in a parallel universe with alternate Targaryens or where House Tully seizes the throne than living in the canon timeline and seeing the past of Westeros on a smaller scale and all the political intrigue. Not for everyone, sure, but I love it for what it is!