I'm not convinced either way. Windows Update is the one opening the dozens of connections (it has to if it's behind a firewall), not Akamai; Akamai's just serving the data. But Windows Update is possibly just calling out to an Akamai library that opens the dozens of connections on its behalf.

If there are also congestion-algorithm shenanigans like the forum post suggests, then Akamai is definitely at fault. But the issue I see is that of connection hogging.