[neilalexander]

> the OS is an excellent point to limit what they can do – including overwhelming your network interface

One might even call this "congestion control"!

[lxgr]

No, congestion control in the network sense is about congestion at choke points in packet networks due to higher inflow than outflow rates.

While you're still on your own host, your OS has complete visibility into which applications are currently intending to send data and can schedule them much more directly.