You're confusing redistribution with scraping. Scraping publicly-accessible content is legal. Redistributing it is not (at least not in the US).

Google scraps webpages as a core competency.

Google also adheres to the robots.txt standard. Most of the scrapers I block don't.

Not correct. Google will completely ignore the rules in robots.txt if it deems it acceptable. I think there's a link to this somewhere in this comment page.

They do not index the content but might add the URL, correct. You can have a meta noindex present and they won't index even the URL.

Putting it online allows me to scrape it, but not to republish it.

I might just want to train a neural network on extracting data out of websites, and, for that usecase, wget -m every website I can find.

How I use the data you present to me, as long as I don’t republish it, is my decision. If you give me a license to read it, you also give me the license to copy it onto up to 7 different media at the same time, and to show it to up to 7 friends at the same time.