Everyone: Please be chill. Also, keep in mind that not every argument or idea you disagree with has to be shouted down loudly. If a proposal (or a counter-argument to it) demonstrates value to enough people then it will gain support and can be refined into something that can reach consensus. If not, then it won't. Critiques of early-stage proposals in particular should be done with a goal of improving them, better understanding their motivation, or comparing them to alternatives. Comments that are closer to just "voting no" on a proposal aren't really necessary.
In disagreements, responding with new information is great, but try not to get in a mode where you are trying to convince specific people (or all people) that you are right and they are wrong. Focus on presenting your own ideas/needs/etc. as clearly as possible. Then people reading the thread (not just the person you are responding to) can judge competing arguments on their merits.
For anyone who wants to improve Rust by designing new features, remember that the bulk of the work is not in coming up with ideas, but in building consensus for them. To succeed, you'll need to spend a lot of time on understanding other people's viewpoints and tweaking your designs and communication based on what you learn. (This includes any concerns from the people who would need to implement and maintain your feature.) This "listening" is the part of the process you'll need to focus most of your time and energy on. If you don't invest in it, then the rest of your effort is likely to be wasted.
[Sorry, this turned into a bit of an essay. This is a topic I've been thinking about a lot as a moderator of this forum—not just in the context of this thread. Please read it as directed to the project as a whole, not just to one or a few people.]