The Medium article[1] mentions a couple - Google prioritizing their reviews above Yelp in search results, Amazon copying third party products that were successful on its marketplace.
RE Amazon... how is this much different than say, store branded items from a grocery or WalMart, or quasi store brands(ie brands mainly only sold in WalMart, like Brahma boots or Ozark Trail)?
> Google prioritizing their reviews above Yelp in search results
This is one reason I use Google. I can view all Google review w/out downloading an app. I'd classify Yelp reviews in browser search as nothing more than an ad.
A quick search for a local restaurant shows yelp as the top hit. Google shows a info box to the side with their own reviews. I don't see a problem with this, and I can't imagine it being illegal. Companies are allowed to cross-promote between their services. Changing this would go far beyond tech companies.