Unfortunately the law has many of these kinds of offences in both civil and criminal legislation and they all depend on the interpretation of both the wording used and the situation and context of their usage, for instance if I said that this site supports copyright infringement I would expect a savvy RIAA lawyer to contact the site operators within a short space of time, I would expect to be contacted personally if I made segregatory or discriminatory statements regarding race, gender or ethnicity, perhaps even age
There is a little used valid legal defence of being stupid that covers many if not all of these "intent" style offences but few folks seem willing to put forth such a defence, despite the fact that a criminal court has to "find" that the accused has either committed the offence or was going to do so &
knew is was wrong or knew it might be wrong, not knowing something is wrong means you cannot have broken the law because there is no intent involved, thus being stupid or ignorant is self defending, amazingly it is also possible in this way to break the law even if what you did was legal if you thought it was wrong
As regards this particular guy he expressed an opinion, perhaps poorly and someone was offended, and that my friends can be all it takes, his valid points where lost in what followed in his post, he became a bad lad only when he spoke in a discriminatory manner towards English troops, I personally think this is a bit over the top as most English folks accept that tempers get hot online, how much better to let off some steam online than have old-style fist fights in the streets but it seems in our modern world of super sensitive folks a line has to be drawn for those easily offended and this guys crossed that line in the eyes of the complainant, and that really is all there is to this.
Speed reading through "the intecepts" own langauge used in this article it seems they are not above ascribing a judges comments and elevating them to "govt opinion" status, hardly fair or honest when reporting on an emotive subject.