What type of link building / back linking is this? Thoughts?

Hey guys... I have recently been surfing some obvious PBN sites used for link building. I noticed this one chain of blogs that builds links through comments on blog articles. The alias is what they are using for linking on the comments... So if you click their name for example, clicking "Claudia" would bring me to another blog or a money site.



Most of the comment names will bring you to another site or blog.

What type of link building is this? What are the PROS and CONS?

Your educated input is greatly appreciated!