I think that probably has a lot more to do with the demographics of reddit and other reddit like platforms. The predominant demographic seems to be white, college educated, american men. Most of the content reddit aggregates seems to appeal to that demographic and reddit's founders seem to be mostly part of that too.

Black, and other minority trans or LGBTQIA2S+ are much less likely to use this platform, or appear in the same physical spaces. There was a lot of work done in the US to try and insure that would happen. This country is very racist and discriminatory. Those practices extend to urban planning and most other things too.