Don't shoot the messenger, because the messenger doesn't know any better:
The way i see it power supplies seems to/ might have some cap(s) before converting AC to DC, those caps might hold current (reserves),
220 volts input will reach output: 24 volts ~6.7 amps perhaps even, 110 volts input wont, perhaps it just does not have reserves to reach it..
this is still good supply but a cheapo, also...being a universal supply the stats are not wrong either.
If i would be buying a supply now, Douk Audio 150W 24V/6A looks really decent, DosThou uses it as i read...
it would be great if someone could measure it but oh well...