BA over the last decade is industrialising at the fastest rate in its history. While there is still obviously way too much poverty, it is overall moving in the right direction with investments in infrastructure and civic improvements. And while I find the current administration reprehensible, it still nonetheless has an excellent democratic structure with officials elected by the population.
Detroit over the last decade is de-industrialising, with basic city services being cut extensively especially in lower income neighbourhoods. While there still is alot of wealth in the city, it is increasingly more unequally distributed. Perhaps worse of all, the city has completely given up any semblance of democracy, and is now run by an unelected City Manager with dictatorial powers.
Overall, the average Detroiter is richer than the average Porteño, but on average life is improving in BA and declining in Detroit.