The showrunners said that Billy was racist. The executive producer said he had bigoted views from his dad. The original script had Billy being more explicit toward Lucas. He said to Max that Lucas was one of this "certain type of people" you stay away from because he was "trouble". That's Racist Speech 101. You can delude yourself into thinking that Billy's coded gay but it can't click that he's obviously racist? Should he have yelled slurs? Lol Billy stans are a ride...
Here’s an article where the Duffers talk about Billy: https://www.vulture.com/2017/11/duffer-brothers-recap-stranger-things-2-will-the-wise.html
And you’re right they do say that he’s a racist but here’s the thing what the show runners said and what was portrayed on screen is another story. Well they may have intended billy to be a racist nothing he did was explicitly so, similarly while they may have intended Billy to be a totally straight stereotypical 80’s male a lot of the way his scenes came off were coded as gay.
A writer or show runner can have all the ideas in the world for how they see their characters and how they intended their characters to come off but that doesn’t mean that’s how their audience is going to perceive it.
There’s also the fact that everyone is going to experience the show differently to gravitate towards certain characters more and interpret scenes differently than how they might have been intended and we’re all entitled to do so. I can understand where people are getting the idea that Billy is a racist based on what the Duffers said, considering he was one of the main (human) antagonists of season 2, and most significantly he was a white guy who man handled a young black boy. That said everything that was presented on screen with regards to Billy and Lucas is definitely open for interpretation as it was never made explicit on screen that Lucas’ race is why Billy had an issue with him.
As far as I’m concerned there is all the evidence in the world to support the fact that Billy went after Lucas much the same way he’d have gone after anyone who Max was hanging with for extended periods of time. This is also an idea that Dacre supports: https://www.newsweek.com/dacre-montgomery-stranger-things-billy-racist-701443
The reason being is anything Max does that she’s not supposed to doesn’t get her in trouble it gets Billy in trouble. While Billy’s behavior towards Max, Lucas and Steve was completely out of line in season 2 it’s clear the abuse he suffers from his father plays a big factor in why he behaves the way he does. And no I’m not excusing Billy’s behavior but I do think it’s okay to try and understand where it comes from.
I think if Billy does have any racist ideas it connects back to Neil. There’s a high probability that Neil is a racist (given his abuse of Billy and his homophobia) and Billy has likely grown up listening to his father use a certain type of language. It’s likely that Billy doesn’t want Max hanging out with Lucas because his father doesn’t like black people and Billy knows he’d bear the brunt of his father’s anger if he found out.
I think a lot of Billy’s lashing out at Max and then Lucas over the situation is Billy trying to take back some control. His first real face to face interaction with Lucas only happened after his father physically assaulted him. I can tell you as a kid who grew up in an abusive home how out of control you feel after being hit. How easy it is to lash out at those around you especially siblings who are favored like Max is (which is highly common in abusive households).
I do think that whatever ones opinion is on Billy and his behavior in season 2 it’s incredibly unfair to write off an abused teenager as a piece of shit racist who can’t be redeemed. Because that’s the logic I’ve seen a lot of people in the Stranger Things fandom use.
We can excuse Kali even though she used her influence over El to get a vulnerable child to help her commit crimes. Then later used her powers to mentally manipulate El in to trying to get to stay (when she made her see Papa)We can excuse Steve even though he acted like he was better than everyone for most of season 1, broke Jonathan’s camera, wrote Nancy is a slut on the movie theater, said some horrible stuff to Jonathan about how he was a queer and his whole family was a screw up, and then got into a physical fight with Jonathan.
Yet Steve became one of the most beloved characters in the entire series and I know there are many who love Kali despite the fact that the Lost Sister wasn’t super popular.
My point is why is it we can move past these characters mistakes and see that they are young people who have changed or in Kali’s case believe they can do better but we can’t believe a teen with a messed up life like Billy is capable of change? That whatever wrongs he’s committed are some how just so bad he’s beyond redemption. I just don’t get it.