Gary Illyes from Google was asked about why he didn't mention links in his desktop to mobile comparison tool post. He said that is because it is "close to impossible for you to check which links are actually deemed critical." So why bother trying to figure out which links are important and which links are not if there is no way for you to do so?
There's also links, but it's close to impossible for you to check which links are actually deemed critical
— Gary "鯨理" Illyes (@methode) September 4, 2017
Gary then added that Google "ignores tons of links" and that even if you collect data from Google Search Console and third-party tools " that you won't know which ones are absolutely critical."
Sure, gathering the data isn't that hard. What I'm saying is that you won't know which ones are absolutely critical. We ignore tons of links
— Gary "鯨理" Illyes (@methode) September 4, 2017
Gary finally added that most webmasters and SEOs would not be able to figure it out but maybe some former Googlers would be able to:
I'm not sure most webmasters and SEOs can say the same though :)
— Gary "鯨理" Illyes (@methode) September 4, 2017
A lot of things in this story above:
(1) Google ignores tons of links, which you all probably know by now.
(2) It is almost impossible for you to know which links Google considers to be important.
(3) Maybe former Googlers who worked on search quality can make a good guess at it.
Forum discussion at Twitter.