One of the large parts of my books is the message, either hidden or brazenly shoved into the reader's face. (I have a novella which has... anyway, another post).
My messages are usually about blindness... people's stupidity, expectations, prejudices, awareness (lack of it). They're pretty obvious to see.
Are you racist? If I say 'Black Lives Matter' do you instantly stand up and say 'All Lives Matter' or even 'Blues Lives Matter'?
Black Lives Matter, by the way. Slavery in the USA was merely transformed into second-rate citizenship where those of colour are seen as worthless by White Americans, and the POLICE, no matter which race they are. What is a White American? An immigrant. Why don't they go back to the country THEY came from? At least they went to the USA voluntarily. And they can go back voluntarily.
Anyway, Harvard has some nice Implicit Association Tests you can try...I did, and I have no bias/prejudice...
So the message in Gubacsi Dulu? Simple, it's prejudice. Against women, mainly. This is the first basic prejudice in society today. Race is the second. Why do women get less pay for the same job, why do women have laws which control the use of their own bodies? It is time for society to change.