But as far as i know this is literallly the first black person ever pictured in warhammer art

It's not the first, 40k art is white as low fat mayonnaise, but like, 5% of the human artwork is of black people.

One of the Emperor’s 20 sons, Vulkan He’stan is black, as are the Salamanders, his legion and all of their successor chapters.

They’ve got their own their own models rules and lore books with pictures of them on the front cover.

There was a recent series of 40k childrens books called Warhammer adventures chuds got big mad about that had a black child protagonist featured on the cover art.

And just generally in the 40k lore and art when they’re depicting humans some are depicted as black.

In universe it’s shown as everyone’s too busy hating aliens and mutants to be properly racist to other humans. What’s really problematic, and a big part of the reason why 40k has so much appeal to fascists, is that the imperium’s extreme violent xenophobia towards aliens, mutants and people with different religions is typically portrayed as wise and justified. There is orders of magnitude more 40k media about the Imperium’s extreme xenophobia saving billions of people from horrible deaths than there isof it causing problems or biting the imperium in the arse. It’s often portrayed as horrible, there’s a lot of “we firebombed this entire city of innocent people to kill 1 (one) genuinely dangerous heretic” or “if you fail in your mission space marine we will have no choice but to glass the entire planet from orbit” but it’s not portrayed as ineffective. It’s generally shown that if that one heretic was allowed to live or the mission failed then the entire planet or star sector would die such horrible deaths they would be begging us for the swift release of an orbital bombardment we would no longer be capable of delivering 😔.

Which is the sort of strength and sacrifice, death before dishonour, murder 100 to save 1000, hard men making hard choices slop fascists absolutely adore, so of course they love 40k and games workshop, being spineless capitalists, are more than happy to feed into it and write a once satirical anti fascist piece of media entirely unsatirically so long as they don’t have to engage with real life fascism. This statement is nice, but unless they seriously re-evaluate how they present fascists (as cool horribly effective ubermensch who do WHAT NEEDS TO BE DONE) they’re not going to impact the portion of their audience that is fascist or their ideologically based enjoyment of the media Games Workshop is putting out.