You keep picking on
[quote], which is the least useful block-scoped example.
But do you really disagree with this example?
Do you really disagree with [spoiler]hiding content here
and hiding a little more content in the next paragraph?[/spoiler]
[quote] example is indeed absurd, but there’s absolutely nothing wrong with the
[spoiler] sample. In fact, the editor toolbar itself will cheerfully generate code like that. (Just try selecting a few paragraphs and clicking “Blur Spoiler.”)
Switching to a correct HTML parser fixes an open bug in the preview pane with misnested
<b> tags at almost no cost to you whatsoever.
Also having to pass extra context into every inline I have is going to create edge case central
What extra context? You already have to deal with this to parse HTML correctly, which Discourse is not doing today because nokogiri has bugs. Just use a compliant HTML parser, convert BBCode to HTML, and it will reduce the surface area of the code you have to maintain.