This article conflated data, copyright law, and contract law.
Terms of Service (ToS) is a contract between the user and the vendor/website owner. The terms may not be enforceable, but that’s a different area of law.
You cannot copyright data (in the US and in many other countries — e.g. https://en.wikipedia.org/wiki/Feist_Publications,_Inc.,_v._Rural_Telephone_Service_Co.) So the issue is that publicly accessible DATA cannot be restricted through copyright and no other (without a ToS or other contract) legal restriction to the data exists, therefore, making web-scraping public data legal.
Youtube videos, audio works — podcasts, songs, etc, written works blog articles, and other documents are creative expressions allowing copyright of those materials. So you can extract the length of the youtube video and other metadata including the title, but not the actual video. You can use parts of the video if you comply with copyright law (parody works, extracts for education, etc).