Wii U only damaged Wii U. Wii itself that audience moved on to smartphones. Nothing was going to save the Wii U from itself. Switch was selling like hotcakes the moment it launched. There were more copies of BOTW on Switch sold at launch than systems sold. Switch didn't suffer from Wii U at all. Wii U suffered from a worn out label. Bad hardware and marketing. Plus Nintendo working on 2 consoles and outdated 3rd party relations. All of that was fixed with Switch. If you want brand damage look at Xbox One and Xbox brand never recovered.