Wikipedia DOES have some bias towards democratic views, in some subjects. In immigration topics, it is more slanted towards republican views though.
But overall, yes, wikipedia's less edited/reviewed articles are more biased towards democratic values. The more read wikipedia articles that have been reviewed/edited more often are very objective though.
Regardless, I don't understand what that has to do with anything in this context. It is an article, hinting towards Donald Trump being racist and providing several tweets/statements at rallys/interviews that hint to him being racist. It provides proof of it too.
If someone linked me a Fox News article that said "Racial views of Joe Biden" and it literally showed tweets of his statements, videos of his statements etc, it's not like I would go "Fox news is right wing, I can't trust the literal video of Joe Biden saying x at his rally to be true. And I can't trust the literal link to his tweet saying x to be true."