Is this power supply suitable for powering these chip on board (COB) LEDs?
7000W of LEDs? Are you lighting a stadium?
Well, since this project will make you blind, it wouldn't be complete without the risk of electrocution, so let's wire the LEDs in series.
As you noticed, the voltage across your COBs varies with current (and also temperature, and between each COB). So you can't drive them with a constant voltage supply, it has to be constant current. You can, perhaps, parallel them, if they are well matched, but that's pretty hazardous because when one COB fails open, then the driver will send the whole current to the others, so they will also fail in cascade.
So you want to run the COBs at around 2 amps, let's look for a constant current driver that will do that...
Meanwell ELG-240-C2100 looks like it, it can output 120V 2A so it will power 3 COBs in series.
There are of course many more options regarding output voltage: higher means more COBs in series, and more dangerous.