I agree sooo much with what you said and that tag also bothered me when I saw it. Sadly, it really just reflects the way a lot of people see sex workers in rel life. Either they are nymphos or they are victims without any agency. Like no one would ever chose this type of work consciously and aware of the negative aspects ans risks.
Well, there is a difference in showing a patriarchal society and presenting it as good and something that should be protected, with dissenting characters represented as crazy or stupid, and mangas like this, when you see how this society affects women, specially women who do not conform with the ideal of the pure virginal or the good wife. Just because a manga shows a patriarchal society, does not mean it is inherently sexist,it depends on how the story is told, by whom and what are its themes. This work shows how dangerous the MC's life is, how a man could ruin everything for her so quick, how she depends on the men at the same time, and moments when the girls help each other. Is it a perfect feminist work? Probably not. But does it reframe various isekai conventions from a different point of view and showcases certain sexist status quo? Definitely.

I don’t believe this manga is sexist honestly
It is the character’s decision, but it’s also part of our society/reality of women from both the past and modern times
It kind of gives me a perspective of a female side character from some other isekai manga those contains some sort of harem (honestly, most of them do) and it really gives the hint of that from that nerd guy that came down with her
Like others have said, our MC isn’t an idiot nor a mindless, and clearly knows what right or wrong
Ah ah ah dont be telling me “oh but she shouldn’t being prostituting herself!” Yeah well tell me what else can women do back in those days to earn some good money? It’s also her CHOICE of picking such a lifestyle, and she has been through this rodeo before
Another thing is the tag for “slut”
She’s not a slut
She’s not crazy for dick or sex
She sees it as a tool, a way to survive
And she has taken advantage of that
Its understandable that this isn’t everyone’s cup of tea but before going ape shit of because its a “hEnTaI IsEkaI” I just want yall to take a moment and actually read what she’s saying
Kthxbye