People keep asking me, "When is the Bay Area going to hold another Worldcon?" I keep answering, truthfully, variations of, "I don't think it should until the local environment becomes less toxic."* I don't see a lot of things that make me think the necessary changes have happened yet. Oh, maybe some of them, but the toxic elements are still there. (Incidentally, I don't see anyone else emerging who seems interested in drowning himself in personal debt to do the necessary work. The previous two Bay Area Worldcons came near to financially ruining me and at least one other person. Anyone else want to try carrying that anvil into the swimming pool?)
When I co-chaired ConJose, I managed to antagonize a whole lot of people, most of them local to the Bay Area. I think that in a whole bunch of individuals' cases, I had the choice of being liked or of getting the convention done. We couldn't have done it both ways. I put the convention first, and I'm better aware of the consequences than certain people think. While I'm flattered at the respect I've received in worldwide conrunning circles, I also know that I'm all but persona non grata in a number of local circles. As someone who wants to be liked, it hurts me more than you'll ever know that the price of getting the convention done was the friendship of those people.
Here's a quote from the penultimate issue of Emerald City:
There is, of course, a matter of committee culture here. Interaction’s staff were very good at cross-departmental communication, at least the divisional level which is where I worked. I recall from ConJosé that attempts to comment on what another department was doing were often greeted with fury by the people responsible for that department.I think that's a fair assessment. Had I taken the choice of "not hurting people's feelings," while trying to manage ConJose, then fairly significant pieces of the convention wouldn't have happened at all, or else they would have happened much less well than they did. As it was, it was a pretty near thing, and I'll go to my grave frustrated over the things that went wrong or at least went very mediocre as far as I'm concerned.
I'm not saying we couldn't have another Worldcon in the Bay Area, or that it couldn't be well run. But I think it would have to rely upon "outsiders" -- people not part of the regular Bay Area conrunning circles -- even more so than the previous two did. The only other way to avoid the toxicity that I can see would be to try for one of the existing conventions to try running on their existing management structure, rejecting any outside involvement and just trying to run things at Worldcon scale out of their own resources. Neither alternative sounds very attractive to me.
*I realize that this doesn't really answer the question posed. Another indirect answer is, "I know when I'd bid and what I'd do to maximize my chances of winning another bid sometime before 2020." To anyone with an understanding of fannish politics, I should think the answer is pretty obvious, and I leave it as an exercise for the student.