Something VERY SH**TY goes here.
The X1 picure is in LIMITED range 16-235
and PS4 is in FullRGB 0-255 range.
You can check "black" in any picture program - even MSPAINT by picking up colour at the up/down borders.
It is 16-16-16 (RGB) and on PS4 side 0-0-0
The same with "white" 235-235-235 vs 255-255-255
So
A) X1 Destiny was GIMPED by Bungie (Sony deal) - not very likely IMHO
B) X1 has a bug
C) Gamingbolt's guys are LAMERS and DISABLED Full range RGB in X1 options....
D) The are crafty bussinessmen and they are LYING/DOING above on purpose to GENERATE website hits