1.4.10 Reflow

I wonder, given the advancement of technology and the significant increase
in pixel resolution on devices since SC 1.4.10 was first drafted, whether
it is time for a modification of the requirements.

The justification for 320px is stated to be because:

"320 CSS pixels is equivalent to a starting viewport width of 1280 CSS
pixels wide at 400% zoom."

At the time this criterion first came into force, 1280px was a fairly
standard laptop screen size. Also, 320px was a standard mobile resolution 7
years ago. However, neither of the above now stands up to scrutiny.

The standard monitor resolution is now 1920px and the lowest resolution one
can find on a mobile device is 400px.

400% at 1920px is 480px.

Requiring no reflow down to 320px is therefore out-of-date for today's
devices and to encourage stakeholder support I wonder if we can increase
this to either 400px or 480px?