There is an awful lot of media hype over human rights and much of it is ill-informed. The media are the first to raise alarm when cases such as the one quoted at the start of this post come to light. However, they fail to report on the many cases which are an actual benefit to the general populace (granted they are few and far between but they do exist)
The key issue here is that The UK does not have a written constitution nor a modern bill of rights. Unlike many other countries (notably The US) legal issues arising from the wider area of human rights require the legal eagles to invoke The ECHR because the lack of our own written constitution/bill of rights dictates that this is their only recourse. Sadly, the general populace see this as yet more interference from Europe predominantly because that is the route of such legal appeals.
If we had our own written constitution/bill of rights as The US does, such legal appeals would be made through our own courts to assess whether they are 'unconstitutional' (ostensibly against the bill of rights) and Europe would rarely be involved. Of course, we may still see what appear to be (at first glance) perverse decisions but the media would be less interested in waving the 'European interference' flag.
The Tories have been banging on about a modern UK Bill of Rights for years but thus far we have seen nothing. Such a bill would have benefits but it would not prevent apparently perverse decisions such as this one occurring in the future. All it would do is lay the blame at the door of The UK Legal System rather than at Europe's.
FWIW, The US system produces even more perverse decisions in respect of human rights. This is a global issue and not just our little island's problem.
BTW, Article 5 enshrines the entitlement to imprison a person legally found guilty of a crime so, providing the trial is fair, no chance of imprisonment being against their human rights.