I don't think crashes have gone up since banning of the supertuck, so I'd say they would do both. If everyone does the supertuck then you still have to take risks in the corners to get the edge over others. Maybe alpine ski race netting like Vaughters is suggesting could help.
Trouble is, downhill ski courses are no longer than 5km. To fully secure cycling descents is many times more.
It is also really hard to design something good enough. Ski nets have several layers - how do you do that over a sharp drop. Making crashes safer will inevitably encourage more risks. A net that turns out to be inadequate could easily be worse than no net at all.
Maybe the big races could use their influence to add better security to roads generally, but I don't see large-scale temporary netting to be anything other than a distraction.