The guy in blue was heavily overlapped with the guy to his front left (who doesn't crash). The shadows were such that I was confused initially whose wheel was whose. Blue was almost halfway up the other guy's bike, i.e. his front wheel was well ahead of the other guy's rear wheel. Blue went into a hole, he didn't back down, and he got squeezed into the guy to his front left.
Based on the massive gaps around the riders generally (I skipped to about 3:55 so didn't see the rest of it, before or after) Blue was doing a super tight move in a field that wasn't used to such things.
Blue was in over his head. Some bump drills, being on the drops (I know I harp on it but it's best practice virtually all the time, you almost never have a problem because you're on the drops), and knowing when to back down, those are things that would help.
Unfortunately judgment is hard to improve. You can get people to respond a certain way to certain situations but forcing them to make the decision themselves? Difficult to train, if not impossible.
In a weekly race like this (it's a weekly thing?), in an environment like that (parking lot, lots of open space, smaller number of riders) it would be natural to have a rider clinic each week. 15 minutes of bumping drills wouldn't take much time, it would improve everyone's appreciation for close quarter riding, it would improve everyone's ability to stay upright, and bring everyone a bit more into a community if you will. An experienced rider that wants to share their experience and can teach/communicate/empathize well? The whole group would be a foot apart in 6 weeks. You could have the best little group of racers around.
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"...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson