It's not like it's without precedence though. 2003 Tour de France, Stage 9. Beloki goes down hard, Armstrong cuts across a grassy area and eliminates a turn in the route by doing so. Exactly zero penalty seconds added to his time.I agree with giving Froome the same time as Mollema in the end, but there should have been a time penalty regardless for running up the hill w/o a bike. That's a black and white call, and even if the accident was caused by something totally out of his control, you have to take the broken bike w/you.
Hell, it's fairly similar for Froome in other ways: a somewhat tight race, where a penalty could decide the yellow jersey, and a competitor for the GC lead (Vinokourov for 2003, Yates for 2016) was finishing well ahead with the potential for a lead change.