Oh, so you don't actually mean what you say, gotcha. Anyway, the people who claim that James and Sirius are bigoted in canon say it's a good thing that it'll make the Marauders look racist because that'll more properly communicate their bigotry to a modern audience. They aren't actually disagreeing with the statement about how the audience will interpret the scene, they are just using it as an argument in favor of the casting rather than against it.
No, I meant what I said (and I wasn’t referring to whatever fans that agree with the casting/change, it’s about those against it). Those who make that statement of the Marauders now looking/being racist are usually, from what I’ve seen, those who think the Marauders were never bullies, held no form of bigotry, and were in the right (even just a bit) for how they targeted Snape because they were doing it for a just cause. They for whatever reason think that James and Sirius were picking on Snape for some morally good reason, instead of what it actually was, which is simply teenagers being bullies, as many are. But now, with the whole “race-swapping” thing, they suddenly have a problem because it forces them to really acknowledge the problematic aspects of their good, beloved characters.
And if a good chunk of the people who read the original scene interpret it as Snape being targeted for his class/looks/ blood, a good chunk of the people watching the show will interpret it as him being targeted for his race, whether or not that's the actual motivation. That's why they are saying "this will make them look racist" ("part of the audience will incorrectly interpret these characters as racist") rather then "they will be racist in this adaptation" ("this adaptation will change the motivations of the characters").
A good chunk of people who read the original source do not interpret it as such, they think Snape was the devil incarnate who deserved what he got or should’ve had it worse, and yet they make this claim, that’s my issue. I’m not arguing that people will not interpret it as racism, some probably will, I’m arguing against those who say the Marauders did nothing wrong, yet are complaining about the change because they’re now doing something wrong (as if they weren’t always).
I’m writing paragraphs about foolish people mindlessly following the crowd instead of formulating their own thoughts, and talking about this weird double standard(?) or situation that they seem to have with white Snape vs black Snape. I fully understand the complaints, but I don’t understand all of those who’re making them (it’s like a “right message, wrong messenger” situation).
(Anyway, looking back, I probably should’ve made my first post more direct and lengthy because I can see how it’s getting misinterpreted. My bad).