Well to be fair - the change implemented apparently didn't fix the troll factor either. The issue was people fishing in progress queues and withdrawing when they didn't get the one they wanted. That part was fixed, but you will always have people not joining a battle for whatever reason. It's not even people necessarily being trolls.
And no, I haven't shifted in my belief that this community overall is fairly toxic. I just reported a post today by a player who told another player to uninstall, stop subbing, go play an offline game, etc. Last night I watched another scuffle between some RP'ers and the folks who clearly think anyone who RP's is a waste of human life. Perhaps I've just been unlucky, being on a legacy server with a healthy population of mercs and just plain mean people. I don't know.
I still don't agree that adding a penalty is ever the right answer when the problem could have easily been fixed by patching up the hole. If YoshiP was truly concerned about players being able to fill dungeons for their friends (which was the original reason to leave the "In Progress" checkbox there instead of changing it months ago), he's clearly made that impossible with the new penalty and must have changed his mind. With that thought - I can't see any real reason to keep that check box there anymore, which means there's no need to have implemented this penalty. He's pretty much broken the original reason he wanted to keep it in the first place, unless the stars align and you are filtered directly into the dungeon your friends need you to help with. I've done it in the past - and it's not sure fire to get an in progress even when queuing a single dungeon. I'd had to withdraw a couple times to get the right one.
So why not take out the whole in-progress checkbox, remove the penalty, and let dungeons fill as they will?