In the first phase of Ukrainian war soldiers were firing a lot of line of sight, it does matter. And especially the IR / night vision opportunities are real.
It's very 'low hanging fruit'. It's ridiculous that that a 20 Trillion dollar Army has 'camouflage' that is very clearly crap next to better camo.
These tests could have literally been run in a day, even back in the 1950s.
Some soldiers, some screens, a few cameras, some changes in lighting and it would have been evident.
Moreover, it's reasonable to be suspect in whether an organization that can't handle such a basic R&D task is going to be able to handle the more complicated things.
There are, it seems, a few aspects that went into the seemingly-obviously-poor decision to go with UCP.
The first is that the criteria that appears to have been most important was performance in near-IR (i.e., night vision). Humans can't see in NIR themselves, so it's not readily apparent that the UCP is actually pretty good camo in NIR conditions. It's pretty atrocious in visible light, though.
The second is the requirement that the camo pattern be good in all environments. And "standard" woodland patterns to be utterly horrendous in sandy desert environments, while desert patterns do similarly bad in woodland environments. And you can see how something like the UCP might score well--while it's not a good camo pattern for any visible pattern, it sticks out less than a standard woodland in desert or vice versa. Of course, there were other patterns at that time that performed strictly better than UCP in all environments (save NIR).
The main kicker, though, is that the winning pattern seems to have been constructed out of elements of all the participating patterns... with no follow-up work done to make sure that the resulting combination actually worked. As you say, this is where some tests would have saved an awful lot of embarrassment, and my suspicion is these tests were not run for either time or money reasons. (And yes, this is a false economy here, but it's one that I can really believe bureaucracies pursuing).
There is historical precedence for this kind of short-sightedness however: the Mark 14 Torpedo, the main torpedo the US used in WW2. Which didn't work, and the Navy's Board of Ordnance took a couple years (and ultimately an unsanctioned live-fire test demonstrating that it didn't work) to be convinced that they actually didn't work rather than the submariners being packs of incompetent morons.
It's very 'low hanging fruit'. It's ridiculous that that a 20 Trillion dollar Army has 'camouflage' that is very clearly crap next to better camo.
These tests could have literally been run in a day, even back in the 1950s.
Some soldiers, some screens, a few cameras, some changes in lighting and it would have been evident.
Moreover, it's reasonable to be suspect in whether an organization that can't handle such a basic R&D task is going to be able to handle the more complicated things.