Agree, open should be the only mode to affect any BGS or other metric, if its fair for pp it's fair for all aspects of the sim, markets missions etc. Make open only & subscriptions to enable better pvp interactions.
It WAS NOT fair for PP to be both Open and Solo PG, because of the undercutting issue - and that's what this change is about and NO OTHER REASON.
For PP to have any real meaning and working mechanic it requires it be locked to just ONE mode so that opposing factions can actually SHOOT AT, those opposing them.
Open is the one where it gets the most benefit, so OPEN is the one it was decided to lock it to.
There was no other decision factor involved, all you Open players who think you've won some sort of victory, NONE. It was a simple choice. How do I know this? Because what is the point of contesting a system if there's NO ONE ELSE to contest it with?
As for the BGS "markets" - what markets? There's no active market to be manipulated here, and no information if it'll ever become one.
Next you'll be saying CG's should be "only open", just to give the PvP idiots something to shoot at - right up until you remember you can all be blocked, and the instances are so small you can't force an engagement without the other players consent by NOT blocking you.