First, let me tell you this is not at all true…

Platinax article accused popular Linux distro such as Ubuntu, Trustix, and Suse for sending email spam. From the article:
Some Linux distributions – specifically Ubuntu, Trustix, and Suse – stand accused of sending potential email spam.

This is because once signed up to their email lists, it is next to impossible for users to unsubscribe.

a) That is plain stupid argument. Almost every list has an option to unsubscribe, at the bottom of email.

b) You can always visit project web site, go to lists and unsubscribe

I strongly believe Linux users are little or more smart than average PC user. Period.