Apologies if I’ve missed mention of this somewhere above, but why isn’t "[[…]]" the least bad option for syntax?
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Link: "[[Note with \"Double Quotation Marks\" in Title#Heading|Display Text]]"
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is valid YAML. Ideally Obsidian’s wikilink autocomplete function would detect that the context is a YAML header and escape the necessary characters.
Wikilinks in YAML headers simply being Command-clickable in edit mode would go a long way for me.
See also: Can [[wikilink]] in YAML ever be “done right”? NO. But there could be a “route of least pain”.