I'm not sure if it is like that in all muslim countries but yeh def sux when you need medical care and can't be seen to because you're of the opposite sex.
It's a culture moreso than religious practise and those things don't tend to change overnight however I do believe people's views are evolving.
The hijab culture isn't entirely toxic and modesty will differ between diff people even of the same culture. I think there is some hostility and some "toxicity" but there is also liberation. I know it sounds like an oxymoron but it all depends on what eyeview you look at.
I don't know how hijab builds sexual repression? Sexualisation happens with or without a hijab culture.
It is toxic because instead of teaching men more on self control and respecting every woman; it teaches women self-shame, that their bodies are problem and that the burden of preserving the family and society honor lay upon them.
Society/cultures teach that, you don't need hijab for that. Society teaches women are second class citizens designed to serve men. Only good if they are pretty, subservient, meek and willing to sacrifice themselves to men's needs and/or children's upbringing as well as being content with the graces they've been provided with. Forget ambitions, goals or dreams, they're only ok if they fit in the man's vision or goals and dreams.
Instead men and women need to be taught to respect each other and their differing attributes and acknowledge that yeah someone might be attractive but there are boundaries in life.