And you're forgetting the double parking, bad parking, standing cars, building construction, street construction, etc. Streets of Manhattan are chaotic. Trust me when I say that there is often not any room for motorcyclists to filter past cars, especially not when bicycle lanes are present.
It being legal or not isn't the issue; it's not possible.
A minimum width lane really doesn't leave enough room to lane split. It works in places like California because they have significantly wider lanes than the minimum required almost everywhere.
That's not true. An experienced motorcyclist could filter through most US cities. Most people have no idea how small a gap a motorcycle can fit through.
And you're forgetting the double parking, bad parking, standing cars, building construction, street construction, etc. Streets of Manhattan are chaotic. Trust me when I say that there is often not any room for motorcyclists to filter past cars, especially not when bicycle lanes are present.
It being legal or not isn't the issue; it's not possible.