As you know, in March, Google officially turned off toolbar PageRank for displaying, well, it went dead in mid-April of this year. But that doesn't mean Google doesn't use PageRank internally, they do.
Gary Illyes of Google was asked this and he said yes, PageRank still matters. This was posted on Twitter:
@gouravrao15 yes
— Gary Illyes (@methode) August 2, 2016
I am not sure why some feel PageRank wouldn't matter. It is probably still one of the most important aspects of Google's rankings with content and relevancy. But yea, PageRank is still heavily used by Google - they just don't share any scores with us.
Some history on Google's toolbar PageRank woes. Google has been killing off PageRank in the toolbar for years and years. In 2007, Google asked webmasters for feedback on removing PageRank and then in 2009, Google removed showing PageRank like data in Webmaster Tools (Search Console). But in 2013, Matt Cutts told us Google probably will never kill off PageRank in the toolbar. Well, Matt is no longer there and it was done. Then in 2012, Google stopped updating external PageRank by accident updated PR in December 2013. Since then Google told us time and time again that Google will never update PageRank in the toolbar again.
So yes, PageRank matters but Toolbar PageRank is dead.
Forum discussion at Twitter.