I can understand the argument, and it was one that I had a lot early in the Blair administration.
At that time, the Tories had pushed unemployment up and up, and for many who had given up hope of getting a job, disability benefits made sense (and of course, being unemployed for a long time can take its toll on your health). The Tories had been happy for the unemployment figures to come down, but do we really want to leave these people behind?
I don't have any hope that a Tory government is considering this for caring reasons, but if the numbers have increased at the same time as the opportunities to work from home have become available, then I'd consider it the state's responsibility to do everything they can to help people from incapacity benefits and into work.
The key word is HELP, but given the links between poverty, inactivity and isolation with poor health, I'd hope that it's something any government would target.