It's all down to technical debt.
Xara has relied so long on keeping the desktop applications there as cash cows that it is now inconceivable to it to rework the product into a more modern guise as all of that would show no visible customer benefit.
Most if not all of the third party products are stale as well so let's all pretend it not there, spend the money on Xara Cloud and hope we get away with it.

Ever more the cynic,
Acorn