It would be a winning battle, since it is less work to blacklist than to make a high scoring site.
I guess Google Search internally is a mess. Maybe they have no clue what they are doing or have some really bad directors and lower managers messing stuff up.
Maybe there are so much blackbox ML called from 1000s of Perl files that the engineers don't understand what is happening.
I suspect you're right about how much of a true understanding they (at google) still have of the behaviour of their search engine.
There are no Google adverts on GitHub, Stack Overflow, etc but there are on many of the copycat sites.
It blocks copycats and hide them from multiple search engines. You may also use the list with uBlacklist.
If they immediately blocked these sites then Google would get a lot of flack for censoring the web.
I don't like these sites as much as anyone. A while back I even tweeted about[0] having a dream where I wrote a browser extension to intercept and redirect these copycat sites to the real site.
In my mind this falls into the same category as phone spam. The phone networks could block these but how would you feel if you knew your phone company was auto-filtering incoming calls without you having any control over that? It's a very thin line.
Hopefully one days algorithms will be smart enough to auto de-rank copycat sites or blatant plagiarism so they don't show up on the first page.
[0]: https://twitter.com/nickjanetakis/status/1473671136928018434
Also, their ranking algorithm is extremely complex. To suggest one complex algorithm is censorship and another is unbiased search results is to have a very naive understanding of how search works.
So... if google creates an algorithm to detect copycatting/plagiarism it's okay for them to deploy it, but it's not okay if they do it by hand?
No, I thought more about my comment a day later. I don't know what a fair answer is. Being ranked on page 216 by an algorithm or de-listed manually is basically the same outcome.
I makes me wonder how Google can mess this up.
There just seems to be a load of imitation sites now, like 6 different wrapper sites for GitHub, 8 for StackOverflow, a couple for GitLab, something aggregating a load of forums - so the first couple of pages are the exact same content - just from 15 different sites that copy the originals.
At least going with a community site there tends to be actual discussion and or useful links to the relevant content