The link search operator (link:example.com) hasn’t provided good results for several months. Google’s John Mueller recently confirmed that the link operator should not be used anymore:
@kunjan_13 @methode @rustybrick would probably tell you not to use the link operator in search. ?— John ☆.o(≧▽≦)o.☆ (@JohnMu) 11. Januar 2017
A free a link analysis tool
If you want to check the links of competitor websites, the free link analysis tool OpenLinkProfiler.org is a good alternative.