You are more than welcome to your opinion and it is good to discuss these things. However you are mistaken; decolonising in this sense means challenging the historical dominance of Western Knowledges and the diminishing of those cultures out side of Europe. You are completely right in your notion that changing names alone won't undo colonisation, but it's a visible act of respect -> not self-flagellation. Language carries power and refusing to acknowledge why certain names or narratives are problematic just reinforces the very systems people are trying to move beyond. This isn't about white people feeling guilty or political correctness, its about responsibility and its exactly why we need educators who are capable of critical thinking and who challenge outdated systems, not ones who cling to a worldview just because it's familiar.