/Counting/ delimiters isn't necessarily any easier for our brains than measuring indentation.
However, it is (at least for me) much easier for your eyes to line up two delimiters then a keyword/function call/literal/whatever and the end of the block it introduced when that block's termination is implicit from indentation. With the delimiters, I have two similar things to line up visually. With indentation-significant, I have to line up a delimiter with blank space, which is difficult.
However, it is (at least for me) much easier for your eyes to line up two delimiters then a keyword/function call/literal/whatever and the end of the block it introduced when that block's termination is implicit from indentation. With the delimiters, I have two similar things to line up visually. With indentation-significant, I have to line up a delimiter with blank space, which is difficult.