Maybe it’s my misunderstanding of the Cambridge dictionary definition of ashamed which describes feeling guilty or embarrassed about something you have done or about a quality in your character. The key word is you. To say Stranded Hatter should be ashamed suggests he had something to do with it but as he didn't it's not his to be ashamed about but like all of us he should and does find it shameful.
The outpouring of white shame reminds me of religious confession in that the act itself is meaningless because it’s what you learn from everyone's misdeeds and the corrective action you take that matters. I think these statues could have become a positive educational opportunity.