Morally questionable maybe, though I'm going full circle and going to say scamming is as well.
edit: The name was posted in public whois info. That basically means you handed out your data to the public anyway. Everyone on this forum would be able to acquire the location from the information he found.
Would it be ok for me to make a blog post with their home address on it, just because it's publicly available? I don't think so, even if they did something scammy.
Apparently it is illegal since the start of this year (in the Netherlands, as it is where the article is from) since may 2018 as the new AVG went into effect and it is considered personal data which requires approval for publishing.
... because it is wrong.
> but yes. Unless you are exiting violence or defamation is your goal.
What other goals would you have though? To cause embarrassment or inconvenience would count as harassment or bullying which are not legal in most jurisdictions.
What good reasons can you think of for publishing an individuals address without their permission?
It being able to be found elsewhere adequate justification: if it is that easy to find then what is your reason for republishing?
With regard to your edit (that happened while I was typing), legal concerns aside are there any morally justifiable reasons that spring to mind?
Since I assume most swatters are 12 year olds, that means they are less likely to know that Whois exists, therefore more likely to have the info because this author posted it.