I want to point at the start of a statement/expression, ask "where does this end?", and get back a single, general answer, like "at the semicolon" or "at the corresponding closing parenthesis".
That is what punctuation is for. Imagine reading an english text with no punctuation, where the author just made sure to end a line wherever he wanted a sentence to end. Do you really want to stop at each line end and have to answer the question whether it ends the sentence?