Google loves sites with high authority like YouTube , Seznam , or Medium . It knows that they are probably not spam or a scam, and it likes to show people results from these sites.
Moreover, the trend is that authority has increasingly greater value in the eyes of Google.
That's why it definitely makes sense to deal with parasitic SEO.
Why?
Spam resistance
If you bought a new domain, added 1000 links to your site, nothing would happen. Google would saudi arabia phone number data never include such a domain in the search because it would easily recognize that it is spam.
If it were a domain that you have owned for some time, Google would start to consider it spam and delist it.
It's different with parasitic sites.
Google, YouTube, and Medium don't list. Thanks to that, you can still have 1000 concentrated links from these places... and these links can actually help you.
With parasites, you can also get away with over-optimization, keyword stuffing, and other techniques much more easily that you would have a hard time getting away with on your personal website.