The sticking point is, for me, that a player in Open is not guaranteed to encounter any extra risk at all - and, even if they were to be instanced with another player, the other would require to be hostile, skilled enough to pose a threat, in a ship that could actually pose a threat, with equipment that could effect that thread, etc..
.... plus the fact that, given the size of the galaxy, average player density is of the order of hundreds of thousands of systems per player if not millions.
So the question is not whether there is extra risk in Open - there might be - it is what level of extra risk is actually encountered. Remembering that half of all players are at or below median skill....
Then there's the fact that Sandro mused about an Open Play Bonus for PowerPlay (the Power, not the player) in March'16, reiterated that the musings related to PowerPlay only, also in March'16, and confirmed, when asked, that it was not going to happen December'16. (see my post above:
https://forums.frontier.co.uk/showt...e-brilliant!?p=6191497&viewfull=1#post6191497)