Well of course the court challenge is going to go ahead because this is only a bill and is not law yet.  It could sit on the House of Commons Order Paper forever and may never even come to a vote and during that time the current practices of solitary confinement could continue.

That being said, while most cases of solitary confinement are unnecessary, some are.  Some serious offenders are isolated because they are either a threat to others in the general prison population or they may be threatened by the general prison population.  Even non-violent offenders may be isolated for a period of time because of threats by the general prison population.  In those cases that last beyond two weeks, officials should be required to justify the reasons for putting a prisoner into solitary confinement.