Yes, Google used to have this feature. I was probably one of the tiny percentage of the users who used it. My guess is it's one of those features where very few people used it. So the cost of maintaining a feature like this on a scale like Google search with tiny percentage of users is not worth it.

I think it was a stop gap solution because Google was overrun with spam sites, like Expert Village, before Google did the Panda update.

https://en.wikipedia.org/wiki/Google_Panda

It's still a huge problem. Try searching for a product or product category. For example, search for "best winter coat" on Google. Half the sites are low quality affiliate link farms who don't know anything more about the product than what's in their Amazon description.

Those sites are so annoying. I want some know-it-all moms on a forum telling eachother what to buy - not scam sites pretending to review stuff.

Some years ago I got moms. Nowadays Google seems to serve crap.

These days I just search Reddit to get real people's opinions on a product. Way more trustworthy than Amazon reviews or random blogs.

The URLs usually have a certain smell to them as well. "bestcoat.com", "topreviewsz", "theexpertreport2021.net" etc.

CHECK PRICE ON AMAZON CHECK PRICE ON AMAZON CHECK PRICE ON AMAZON

Isn't that still an issue? For some of the obscure searches I'm still seeing sites that copy content from github/stackoverflow/reddit

Yep! It was called “personal blocklist (by google)”.

I don’t think anyone was maintaining it. So when the SERP changed its layout, the extension broke and Google removed it :(

What do you mean it broke? I am using it as we speak and it still blocks great