You want reality to match the new stereotypes you've created, and then some. You begin to write the world you want to live in.
Black men are usually very effeminate. To the point where most of them act very gay. There are almost no such thing as masculine black men. Black women have begun to really migrate more towards much bigger white and Asian counterparts. White men are almost always bigger than black men, but Asians are giants at an average of 6'10" for any East Asian male. Most Asian men have thick stubble and beards. They look like, in this universe, more like a mix of East Asian and Caucasian. Indian and Middle Eastern men tend to be slightly bigger than white and black men on average, with slightly bigger than average dicks.
As far as white men go, they are considered the smartest. They are dominant in any upper class field such as medicine, chemistry, math, and tech. Asians are great athletes, and are renowned for being great construction workers, jocks, cops, soldiers, bouncers, and they often have a smug and superior attitude that comes with being naturally bigger. Asians tend to enjoy proving how much bigger they are than other smaller races in shows of physical prowess and strength. Asians, Middle Eastern, Indians are all seen as a masculine ideal, so much so that they have their own gangsta look to them. Asian men will often wear chain necklaces that show off their muscles, gangsta clothing and backwards hats, as well as any gym clothes that show off their enormous physiques.
Black men usually get ignored on social media due to their small stature and size, and although they are in all professions, they tend to be totally absent from sports, the objects of pity in gyms, and terrible at sex.
You set your magic writing aside. You can't wait to explore the world now!
You decide to walk around your neighborhood and see if any changes have occurred that you can see right away. A garbage truck is just down the street but you can tell that the man standing next to the truck is practically a giant. He must be over 7 feet tall! He appears to be Indian with a big bushy beard. You blink. This is seen as normal in this universe.
You walk to the nearest convenience store. There are some Koreans there. You remember their family but not like this! The husband, who is in his mid 40s and before looked somewhat depressed and with big bags under his eyes, is now at least 7 feet tall. He looks down on you and recognizes you, greets you from behind the counter. You have to look way up to see Mr. Cho and it makes you slightly dizzy. He has much thicker stubble than before, as thick as stubble can get. Damn Asians getting all the good hairy genes, you think with admiration.
You buy some milk and lottery tickets. You are mesmerized by the slow way Mr. Cho moves, and his musculature is, while not that hugely impressive, naturally dominant. He doesn't have to even work out much because he's so bulky by nature. Thick-set, they call it. You stare up at his pecs, which are above your head now. Mr. Cho used to play football, along with all the other Asians. Hell, 90% of football players were Asian these days in the US. They just outmatch every other race in terms of size. It isn't even fair for most white men to even attempt to play with Asians. It's like grown ups playing against children.
You think of a few other places you'd like to visit. The beach, or maybe a nightclub.