I feel sorry for them from what I know about convict history and penal colonies in Australia. The British authorities were very nasty. You could be sent to the penal colonies with hard labour for stealing a loaf of bread to feed yourself. Patrick Logan, the commander of the Moreton Bay penal colony here in Brisbane, was a very vicious man https://en.wikipedia.org/wiki/Patrick_Logan
Ultimately, she ended up having 6 children with 3 different men. The first was a guard on the transport ship - I doubt you could define 'consent' in that situation, and the 'relationship' ended when the voyage did; her second 'husband', my great grandfather, was a fellow convict on Norfolk Island - he became the colony's first hangman! and died there before the colony was evacuated to Hobart, where her third (and only legal husband) seemed to help her raise the family. Until he drowned in a ferry accident.
Of course, who knows what her life in London was like or may have been. 220 years on, I'm certainly glad she (and a dozen other branches of my fanily tree) ended up here.
Having said that most convicts upon emancipation were allotted land and tools (and sometimes convict help) required to cultivate farms.
On the other hand, these songs could be disingenuous romanticizing of criminal lifestyles. Just look at the narcocorrido genre in Mexico -- two centuries from now, do you think it would be reasonable for people to examine then and think that their subjects were decent, hardworking folk being unnecessarily hassled by The Man?
For quite a long time a lot of events were written down and communicated via Broadside Ballads: https://en.wikipedia.org/wiki/Broadside_(music).
Broadside Ballads often described events and people and were usually written to be sung to common tunes that the public might know. A lot of the ballads became folk songs over time and the lyrics/stories/tunes changed, but they're often still traceable back to their roots. So where a ballad might describe an event pretty plainly, the songs derived from it will most likely embellish and romanticise it.
The Bodleian Library in Oxford has an online collection of Broadside Ballads that is very well maintained: http://ballads.bodleian.ox.ac.uk/. I found the following whilst seeing if there was anything related to Moreton Bay, and although it only shares the namesake, this is quite a good example of how the ballads were written: http://ballads.bodleian.ox.ac.uk/static/images/sheets/15000/....
A good example is the quite famous folk song Scarborough Fair, which is one of a number of variations descended from a ballad called The Elfin Knight: https://en.wikipedia.org/wiki/The_Elfin_Knight.
My knowledge is mostly limited to English and related folk music, so I'm not sure if there's anything similar elsewhere, but it's certainly an interesting subject and it can be pretty fun to take a song and see if you can find out the original story :)
https://en.wikipedia.org/wiki/The_Fields_of_Athenry
Though it's been co-opted and changed into a sports song by some football clubs.