Earlier quoted context omitted.
It's a bit like the Dvorak keyboard problem. It's slightly better, but too much of a hassle to bother with. You need something between 2x and 10x better to displace an entrenched incumbent.
I think a better music notation system would easily be at least 2x better for beginners. A rationalized system could mean 100% of kids learn to read and write music, and anyone could understand how to play an instrument like a piano from music (even if not able to do it at full speed). My point was that it could be 10x better, and it wouldn't lead to a switch. The decision-makers aren't the same as the people whom it…
That's not to say many folks don't have trouble with notation, but if I had to place a bet, almost any notational system that abstracts away from letter names or (in the case of piano) keyboard positions will pose difficulties.