I just wrote a long reply going into some detail as to why FF can’t be optional for ranked matchmaking… but then it occurred to me that we are probably not talking about the same thing. I wish the thread author would have specified what matchmaking they are talking about. As it is, the discussion (and vote) seems to have little value because people interpret the question differently.
The most sensible choice is to have FF always on in competitive (ranked) matchmaking and FF always off in casual (quick play) matches. Custom servers can have an option for it. If you make it optional for matchmaking, then if anything it could be an option for quick play (which I would not call “matchmaking” since it just puts you into an FFA server, but it can be seen that way).
From what I can tell by what the devs are saying, this is more or less what they are planning to do.
If you don’t like FF, then of course you are not a competitive player anyway since all tournaments and such already play with FF on.