I think this is partially, and unfortunately, true.
There is certainly space authors to question or propose things in the HTML specification through github issues. At the same time, since implementation is important, if there isn't uptake from browsers we are likely to suggest it move to incubation - i.e. here on discourse, or if a proposed specification is already available to the WICG repository.
Regarding Ivan's question of how friendly discourse is as a discussion platform, I think the true answer is "as friendly as the people who are there" - it doesn't take much technical skill to use, but the people involved will determine the value and tone of the discussion.