Yeah your right but cutting and pasting every text element is a right chore, every title, every keyword, every alt text, page name.
And then when you look at the page you realise you’ve written too much for one section so back to the word processor goes a whole section.
Check as you type may not be necessary but a site wide sweep on a menu before publishing - that would be amazing. I can’t be the only one who gets emails about spelling mistakes that made it past vetting. Especially as the only way to easily share with remote proofreaders without risking versioning problems is to just publish it.