The point of asking a question on stack exchange is to create a question answer pair as the whole goal of stack exchange is to create a repository of high quality question answer pairs. If it's not possible to select an answer to a question then it isn't a relevant question for stack exchange.

And the point of this repository created by users for free is to sell it to a 3rd party I suppose?

Why would anyone other than undergraduate students spend their time on such a site

At least in software development, SO is/was very useful, as they provide a curated repository of Q/A where the answers follow the current state of tech.

Every time I started out learning a new framework, SO would be tremendously helpful, because in software development, you mostly have questions that have correct and incorrect answers.

I said SO but I should have said SE in my case - it just doesn't work for research fields because these especially are all about exploring unknowns, yet SE doesn't allow this...

Maybe software engineering is all solved and there's no more ambiguity left to be discussed.

I think the point is to just spread knowledge, in principle at least.