Hello, interesting question. As far as I understand it is not needed as long the cookies are used to maintain the main functionality of a site. I don’t know if anybody actually can tell what that means exactly and whether it applies to Vimeo too. I also don’t really know how it works in general with iframes. 🤔
After some research, i found a solution with services like https://www.osano.com/.
But i won‘t use it, the Code always connects to the company‘s server. So i don’t care anymore about Cookies. 🤷♂️