Gotta say I also miss having more merit-based discussion. Sometimes the wording is difficult and comes out wrong, which can lead to run-ins or hurt feelings, but we can do it without those intentions and it's not "gatekeeping" or "telling someone what to want." Characters have pros and cons, merits and lacks thereof; anyone is free to advocate for any character for whatever pros and/or merits they perceive, but likewise anyone is free to advocate against said character for any perceived cons or lacks of merit. It just needs to be done respectfully.
"Shoot down wants" I in this context I am going to interpret to mean "explain why I don't think that character/idea should happen" rather than "prevent people from explaining why they think it should happen."
Smash speculation has always been a cesspool of desire and likelihood; they bleed into each other inevitably. It's good to separate them as much as possible for the purpose of having rational discussions about likelihood, but it's also important not to let likelihood totally govern what one would like to happen. I don't think you should be so afraid
of your biases affecting your expectations, unless you really don't think you're mature enough to handle it if things don't end up going the way you wanted and/or expected...