I think the argument is that they were using the product in a workflow that wasn’t considered valid. They depreciated the old workflow because it wasn’t even considered as a useful thing. The plans were always given days of the week to complete them on. Envisioning it as a list of things to do in order at your convenience is an imagined anti-workflow.
Training is always done in the context of timing. The plans were always presented in the context of timing. That people were able to use it as a list of workouts was a quirk of the UI that the implementors presented.
They have stated that they are going to give ‘something’ for people that don’t want to plan their plans and just be told what to do. Considering the way that it was being used was probably doing more harm then good (oh you haven’t ridden in a week? do pettit so that you can recover from that vo2 max session 7 days ago) I can see why their motivation for ‘making it work the old way’ would be low.