I don't think Meghan planned a whole 'become royal, then hotfoot it back to America with the title' campaign - because she's clearly not that strategic.
I do think she was either misled/badly informed or ignored what Harry and other people were telling her about the life within the Royal Family.
A lot of her misconceptions come from being American and ignorant of the level of protocol and 'rules' that the royal family and the wider aristocratic circles run their life by.
She said a line in the Oprah interview that I thought was very telling "it's not like you expect / see in the movies".
And there was also the incredulity that Oprah expressed at the size of Nottingham Cottage.
From the outside (to an American) being a member of the royal family looks like being an A list Celebrity on acid.
But it's a very different day to day life than Hollywood A listers - look at the type of house Meghan and Harry bought when they had their freedom.
She preferred the private jet to Elton John's villa rather than muddy walks and group parlour games in rainy Balmoral.
The glossy tiara events are few and far between - and even then you have to sit next to and entertain the Polish foreign minister's spouse for several hours after you've had your glamourous photo taken.
I really think she (and Oprah) thought life was like The Princess Diaries - montages of fabulous outfit and jewelry changes, huge fancy castles etc. But the royals don't really 'live' in the fancy parts of the castles and palaces - they keep those reception rooms for official business and live down the hall in cosy, dog haired covered, homey spaces. Or those who love art and fine furniture live with very formal, irreplaceable antiques that can be traced back for generations.
Look at how much grief the Middleton's got for their 'middle class' tastes - Carole was accused of being twee and bourgeoisie in her house decorating style and blamed for doing up Anmer Hall to be like that.
I'm sure Meghan experienced even more snobbery about her American tastes.