Any such tooling tipping point would likely make the syntax of the underlying representation irrelevant. What to view the logic in tree notation? Or how about with the parens? Or the parens, but so faint you can't see them? Or collapsing aspects of the code you're not currently concerned with? What gets eventually transformed into the 1s and 0s executed by the machine, and its various representations along the way are really not the concern of the person writing at the top of that stack, at least not most of the time.
Personally I find the added vertical space by tree notation very distracting and that it breaks the scan of my reading. But that's my personal preference, and something that could be addressed with tooling. And that's the point: same thing can be said with the parens of lisp or other editing/IDE tooling.
I happen to like fine-tipped pens, while others enjoy the smoothness of thicker rollerballs. Is one better than another? Do the benefits of one make using it to the exclusion of others a no-brainer? Does my enjoyment of fine-tipped pens preclude others from developing new pen types or new writing implementations all together? Might my evangelism for fine-tipped pens turn people off from exploring the perfection that is the Uni-ball Signo UM-151 0.28mm (in blue-black ink, of course)?
To each their own. Find the medium that best helps you express your message. And that may not be the same for others. And that's okay.