@mkljczk That's not the case: some Mastodon users don't know what Mostr is and often don't realize that they could block the entire instance using the appropriate feature.
As an instance administrator, I receive several requests of this type and believe it's important to provide information on these issues.
I understand that you disagree because you see this post as duplicating spam, but you should also try to understand that this information can be useful to others.