1. This thread should probably be locked.
Perhaps, but not just yet. We like feedback, and someone might present a take that we hadn't thought of yet.
2. The problem with 5e threads is that people take them as a license to engage in what would otherwise be stunningly poor slippery slope reasoning and veiled edition warring
Yah. Folks seem to underestimate how... much we rubbed each other raw over the past months. Even if you had no intention of criticizing any particular prior edition, someone's going to take it that way. We're sorry that's how it turned out, but it is how things are.
Given that virtually any discussion of new possible mechanics can be had without any mention of edition, this isn't really much of a topic ban. If you want to talk about diceless combat mechanics, go ahead and start a thread on "Diceless combat mechanics". Just don't start one on "5e: Diceless combat mechanics"
Heck, I'd welcome discussion about new possible mechanics - let the homebrew roll! It isn't like worrying about 5e now is going to make your current game any better. Talking about interesting new mechanics might, though.