I ran yesterday and was perfectly comfortable. I went with compression half tights under shorts, singlet, arm warmers, cheap polyester knit gloves, and a thin hat. Also Smartwool running socks, but they got waterlogged and hurt my feet.
I was actually colder in 2015, when the weather was similar but less windy. The key difference for me was just never bonking, because the cold starts to creep in when your effort drops. I wonder if the relatively slow pace was part of the problem for elites, since many wouldn't have been working hard enough to stay warm on their own.
You said it better than I could, but that was exactly my outfit yesterday (minus the shorts, I just wore half tights). I was pretty comfortable yesterday temperature-wise until I hit the finish line and had to walk back to the hotel. (Although props to the 2 guys I saw jogging back to their hotel after the marathon)
This seems like a pretty standard setup. I've never worn arm warmers but your setup is no much different than long sleeve form fitting shirt, gloves and a hat.
That's warmer than a jacket? Although you were closer to what Yuki was wearing.
I wouldn't say it was warmer than a jacket, but a jacket would've been more drag into a big headwind.
The key was to judge your effort so you didn't wind up slowing. Once you slow, you aren't generating enough heat to avoid hypothermia, but as long as the effort is good the heat is there. Maybe the elites with very low body fat were worse off, though.
The average African elite is about 105 lbs (averaging men/women) and low body fat, PLUS they don't train in the rain. Even Galen,Shalane and Molly are skinny/small enough that they shut down.