You also have a huge problem with everyone accusing others of bad intentions.
Until folks set the bar somewhere other than perfection, you'll never avoid the problem. There will always be someone, somewhere designing a t-shirt someone doesn't like.
For me, you'd be better off focussing on more successes and fewer failures. You aren't perfect and never will be, because you are human and the world isn't designed to make it possible. You aren't better than others. Nor are you worse than them. You've done some decent things along these lines. The US not only began with slavery, but it fought to get rid of it. The US not only had its Jim Crow period but also its Civil Rights era. People of different ethnicities all make contributions that produce a more interesting society. Think of take-out but remove Chinese, Italian, Thai, Indian or Japanese from the list of options. How many hot dogs can you eat?
I wish folks could look in the mirror and see themselves as neither hideous, nor beautiful, but human, with the lines of experience embedded in their faces. Understanding those lines is what makes for character. But you can't unmake them. Nor can you prevent them accruing.
Do you think endless, competing claims of victimhood make for a stronger or a weaker society? - Because everyone has something to complain about, if that's the path you choose. It's no good saying white people can't complain but black people can. If the most profitable path is to claim to be a victim, everyone is going to head down that path.
An alternative is to decide not to do that all the time about nearly everything.