My son is all boy! He is all about all things Batman, Black Panther, Lightning McQueen, and anything to do with large trucks or first responders. However that is not because of anything my husband or I have forced on him. One of my first Amazon purchases for him was a babydoll that had his skin tone and some St. Louis Cardinals onsies. Now that he is 4, we let him make a lot of his own choices; we let him look at clothing and pick what he likes (he picks superheroes and vehicles), he spends his own birthday money (cars and sports equipment), we let him pick what he wears each day (sports themed shirts or superheroes, and his favorite pink shorts when clean).
I have gotten some push back from people I know about letting him pick things that aren't masculine. Most notably as a 2 year old he asked me for hair bows. When he was born, he had a full head of hair, and when I say full I'm not exaggerating. My sister expressed sadness that he wasn't a girl because he had the perfect hair for bows as an infant. When he got older and started picking who he liked to play with at school, he went straight for the girls (they went straight for him as well). One day he asked me if he could have bows for his hair, I asked why he wanted bows, he explained that his friends all have bows and he wanted some. So we went to Target and I let him pick what he wanted from the hair accessory aisle. He selected a set with six clip-on bows that were bold colors. He preferred the green, black, and purple ones, while insisting I wear the pink and blue ones. He never wanted to wear them outside of the house, but we never told him he couldn't.
I will admit, I occasionally buy him toys and books that focus on female roles or characters. He has a toy kitchen and loves to "cook" me dinner, but in our house my husband does the cooking, so he doesn't realize that is traditionally a female thing. He has the female counter parts to various characters from movies and shows he likes; Cruz Ramirez from Cars 3, Dizzy from SuperWings, Wonder Woman. One of his other favorite toys is a doll house I got at a consignment sale. I had wanted to get him a doll house because playing with that kind of toy is very beneficial to social and language development as they invent stories and have conversations. It was surprisingly hard to find a house that wasn't pink. I happened to find a Playmobile house with the most amazing 70s mod furniture to go with it. I would have preferred finding a toy that had more racial diversity, but that is a post for another day.