The article states that every time the plugin updates, it automatically opens up a webpage that serves malware. So technically the article is not wrong. NoScript forces your browser to open a malicious page, therefore it can be considered itself harmful.
It opens a page with an advertisement link for "Speedup My PC", not even the article claims that it serves malware, just that it "promotes" it. Going by the description of the detected malware signatures Speedup My PC isn't even harmfull by itself, it just is snake oil with no real use bejoind selling its own license.
Unless you click the link, download the exe, install it, fall for the detected issues notification and then proceed to buy a license nothing will happen.
Now, the question is, do I trust a plugin that serves ads for malware?
BTW any info on when did they start doing that?
If I were to personally inspect every software (and hardware where possible) I use I would barely be up to date on 1995 versions of computing.
I outsource this trust to an aggregation of online communities I believe in. This post dramatically lessens my trust in NoScript.
You have to disconnect from the internet, restart Firefox, let it fail to load the page, then go to the settings menu and uncheck the box.