> Control characters are invisible, using them means changing text editors to display them. They are also, outside the usual ones, hard to type. ASCII ones have Ctrl combos, but editors used those for other things.
Yes. Change of paradigm does require change of tooling. If some legacy tool doesn’t support new format, it’s not a good reason not to use new technology - either tool evolves or a replacement emerges and typing won’t be a problem. Classic formatting commands from rich text (Ctrl-B etc) can be repurposed, for example.
>Also, what is the difference between using some new character to start block and "{" or "\n"?
Any such delimiter has other use in text. Dual use means extra ceremony with escaping and extra complexity. Whitespace as a delimiter has especially bad UX, because most editors don’t understand the semantics and it is very to make mistakes.
