I didn't read the top level comment as dismissive or 'proving it wrong', but rather as adding context, or even being humorous somewhat

I don't understand how calling something "a ship of Theseus in corporate form" or "culture hasn't changed" etc, is not dismissive of the actual comment by the CEO on AI overspending. They dismissed the content of the message by saying IBM's culture sucks, is how i read it. Also things can be funny and dimissive at the same time, they often are.