If you look inside the transforms, you would see that RGB_monitor is based on
Display EOTF :
// The reference electro-optical transfer function specified in
// IEC 61966-2-1:1999.
Part 2-1: Colour management - Default RGB colour space - sRGB
If you look closely, it is taking an image assumed displayable in digital cinema environments and mapping
it with an adjustment for dim surround to the sRGB equation.
Sometimes however, displays that claim sRGB compliance are not really doing that – they instead use an approximation of a gamma 2.2 for the display. This can lead to the appearance of crushed shadows.
The ACES ODT assumes exactly the sRGB transfer function. If a gamma 2.2 is needed, it would be better to start from the Rec709 ODT transform (though it uses a gamma 2.4). and apply a slight contrast tweak.