I was using Ahrefs to perform a link analysis of my site and that of my competitors. I noticed something weird about by competitor. They have hundreds of backlinks coming from blogspot subdomains (example: something dot blogspot dot com). I followed a few of those URLs and found that those links are not in comments. In fact, they are show up on the sidebar in form of the actual site URL. The site URL itself is the anchor text. I noticed this even for some of the biggest known brands like Healthline dot com.
I don't know how they are doing this. In fact, though those blogspot blogs look pretty shady, they have high page authority while some have very high domain authority as shown by Ahrefs. I don't know whether I made myself clear or not. So, I will put a screenshot hoping that it will not violate the rules of this forum.
If anyone has any idea of how this is happening, can you please explain?

I have noticed how my competitor is receiving/building thousands of these links and growing up in SERPs and even domain authority. They have 33000+ such backlinks. Some clarifications and insights will be helpful.
I don't know how they are doing this. In fact, though those blogspot blogs look pretty shady, they have high page authority while some have very high domain authority as shown by Ahrefs. I don't know whether I made myself clear or not. So, I will put a screenshot hoping that it will not violate the rules of this forum.
If anyone has any idea of how this is happening, can you please explain?

I have noticed how my competitor is receiving/building thousands of these links and growing up in SERPs and even domain authority. They have 33000+ such backlinks. Some clarifications and insights will be helpful.