I don't think it's really out of topic. People linked to the blogpost. The service in question is used on the blogpost.
We are a technical bunch. It make sense to comment on the technologies used in a link rather than only its content.
Exemple: candyjapan has this nice comment at the top of their pages sourcecode.
"Hi,
Thanks for reading the source.
If you would like to start your own subscription box, buy my book!
https://www.candyjapan.com/book
It contains information that will honestly be useful to you, such as different
platforms for running box sites like these and even some sample marketing campaigns."
It's only mildly interesting, so you don't create a thread but make a comment about it. It's still relevant to the discussion because the link was to the website. It is however irrelevant to the content of the article that was linked, but that shouldn't matter.
But does it really need it's own thread?
I don't think it's really out of topic. People linked to the blogpost. The service in question is used on the blogpost.
We are a technical bunch. It make sense to comment on the technologies used in a link rather than only its content.
Exemple: candyjapan has this nice comment at the top of their pages sourcecode.
"Hi, Thanks for reading the source. If you would like to start your own subscription box, buy my book! https://www.candyjapan.com/book It contains information that will honestly be useful to you, such as different platforms for running box sites like these and even some sample marketing campaigns."
It's only mildly interesting, so you don't create a thread but make a comment about it. It's still relevant to the discussion because the link was to the website. It is however irrelevant to the content of the article that was linked, but that shouldn't matter.