Who can figure this out?

How does this website have reviews show on the organic search results, search for "organic SEO marketing"

I know Google used to show these in the past, but they stopped.

maybe G didn't stop it at all, but removed it for low quality sites or something like it..

I looked at those sites for that term and similar, the reviews are fake and they use a growth + random function to tweak it slightly over time to make it appear natural. If you look at the source code they are also hiding it using CSS or in some cases putting it at the footer on the far left...

There are a few sites that have been getting away w/ it for months now.

Big G knows these grades and reviews are mostly fake so I don't think they use it for ranking. It might only increase the CTR.

It increased the CTR for sure. But I am not able to see how they are managing to come up with it in Google Search. Trying over it.