Yes guest post backlinks are zero value in 2020 just like they said
Google Toolbar Pagerank Finally and Officially Dead in 2013,
avoid link building in 2015,
Links Are Not The Most Important SEO Factor in 2020 and probably
SEO is DEAD from 2016. I am not saying the guy is lying but he always tells you half truth. The other half truth about that topic/thing you have to find out or read the meaning behind the words he said.
Like when he said
Google Toolbar Pagerank Finally and Officially Dead in 2013 that just means they didn’t want to show the metric to the public or most probably SEO’s so that they could not manipulate rankings. But they are still using pagerank as one of the ranking factors. They also apply and got the patent for pagerank in 2018.
Like when he said
avoid link building in 2015, still people are making links and getting results it’s about
how you do link building not what you do. Methods, techniques and way of doing is always changes from person to person.
Like when he said
Links Are Not The Most Important SEO Factor in 2020 we all know it is not most important but one of the important ranking factors.
So as long as you are getting a link from a site which is relevant to your niche and getting some good traffic and relevant audience which will click on your link for more information about that topic you are fine and good to go.
Hope you got my point. Don't always trust what he says or even what other SEO's says. They are telling you their experiences and facts which they find out while doing link building. Take a reference from it and do it on your own way. When you have your own experience and facts check then only you will understood better. For a reference check BHW My Journey Discussions, you will find a lots of experiences there.
