In December 2016 I noticed that Google was showing fewer and fewer review stars / review snippets in search results. However, the review stars can be generated by Microdata or JSON+LD.
It appears the review stars being filtered away are from websites which use Microdata.
Review snippets are disappearing from SERPs as Google recrawls pages
By using a site:search as outlined in a previous article, we can see that some sites still have review stars showing up in search for a small portion of their pages. The pages still showing stars were last crawled prior to December 7, 2016 (or around that date). Pages crawled after are no longer showing review stars in search.
Confirming my suspicions
To confirm my suspicions I visited the good old Mozcast and selected review stars. Indeed, less reviews are showing up in Google search.
I suspect the downtrend will continue as Google crawls pages on websites it hasn’t visited in months.
The only potential flaw in my theory is a plugin change affecting lawyers using Justia websites, one of the few platforms still utilizing Microdata as opposed to the newer, superior JSON+LD script.
Is this temporary?
This happened in February 2016 and they returned, but in that case, the drop was drastic. This time, it looks gradual and has been going on at least 30 days. That is a shame as they drastically increase click through rate.
I did predict this would happen though – maybe Google read my article on why they should remove the review snippets… 🙂