At that point in time, definitely, like in the comics, you have super rich people that were living in the same city as super poor people, the parents of the rich kid were very against their son going to a public school instead of a private, better one. Even if we are all mexicans, people who are of african or native descent were, and still are, discriminated against for their origin, wealth or both. Both of my grandfathers have brown skin and faced discrimination, for example. Nowadays, i don't see it as much, especially in Mexico City, there is a lot of diversity there, but there is also a lot of crime because not everyone has the same living conditons, you can compare 2 different regions and see the difference in wealth. Truth be told, i haven't visited many cities in my country, so i can't say how things are in most other states, especially the northern ones that are close to the US; where i live the population is reversed, most are from native origin so i have more friends that have dark skin than ones that have light skin, i'm a popsicle because i got burned by the sun so i have clear sections in my body DX.
Comics like these are an interesting window to the past where you can analize how people thought of each other back then, even if there is a clear bias against or in favor of certain groups (like how the main protagonist's mom is a fat black woman who can't read or write and only works simple jobs), i personally find it fun to read the adventures these kids lived, like i said, some stories dealt with tough topics and there is some history represented in them (like how the gang found a dead body while exploring the tunnels the metro was going to run through
). You could buy this comics for like 10$ pesos back in the 2000's, which wasn't really that much money for a kid to ask for.