Yeah, in those days being a maid in a country house would've been one of the best jobs you could get as a woman, even though it was still pretty horrible from a modern perspective. You'd get free food (usually whatever was left) and board (tiny room in a cold basement), and would get the chance to make a lot of connections, I'm sure. Plus, if the family liked you and you weren't a bad servant, they might even keep you on for multiple years! I think Ruby should've touched on the homesickness aspect and the loneliness of it, though - as a scullery-maid it was basically in your job description to be quiet and solitary, and most servants would've been miles away from their homes and families for extended periods of time. It was really demanding and tiring, and your luck would depend on the family you worked for in most cases. God forbid you get a horrible family who mistreat their servants...Just thinking this too. I am a big fan of the 1970s show 'Upstairs Downstairs', and while it's mainly set in the Edwardian era, there's so much info in it about the difference between scullery maids, parlour maids, house maids, lady's maids etc. and their daily schedule (i.e. get at 4:30am, go to bed at midnight etc.). I can imagine the tasks and schedules were even more gruelling in an earlier era like the Victorian age. A lot of things she says actually aren't quite correct either - e.g. all maids would wear a bonnet of some sort, so the emphasis on the bun height is irrelevant.
Plus, does Ruby think that being a scullery maid was a default career for the working class? That role is still so closely linked to upper class contexts that it loses its emphasis.