Hi,

but rel="nofollow" is not about spam prevention, it's about making the goal of spam to do SEO ineffective.

Yes, I agree, as long as the attribute is not used across the board. Let's imagine that everyone always used rel="nofollow" and search engines rigorously respected it, how would the web look and function then? It is the task of the search engines to design their algorithms robustly and without our intervention. In my opinion, rel="nofollow" is the crutch and not the answer.

All the best
Micha