Essentially sublime can't fold ANY languages delimiter unless it's indented vs the starting marker of a code block?
Essentially sublime doesn't AT ALL recognize syntactical blocks of code and add folding behaviour based on that. No block delimeters or keywords are considered.
It's way simple than that. Consider this example:
Syntax: Plain Text
Unless Sublime is aware of language block delimeters, there's no way to consistently handle folding of block in different languages, thus John resorted to this simple solution.
Which admittedly is not perfect and at times is even annoying.