at the iptv66 website, there are some icons of different iptv related devices, and roku icon is one of them, and when you hoover over and click that particular icon it takes you to our
sister site which is a Spanish language site.
It is not a Roku Forum.
It's a Spanish version of iptvTalk, sort of
There is no reason why in particular that the Roku icon is clickable, except that the icons are there as advertising in what can be used with iptv.. You can use roku but as Suport mentioned, its is not a good way to go when using private iptv services and will end for you personally, once roku analyzes the port usages.
Some of the icons seen at iptv66 website have an embedded link attached to them which when clicked leads to that sister site.