Nope. Your ISP just let their handoffs with whatever transit provider Netflix get overloaded which kills throughput. When Netflix pays the ransom to upgrade the links, your videos will stream nice again. Netflix paid ransom to the ISP I use, so my Netflix works well. It has nothing to do with active throttling.

I don't think there is any explicit shaping / throttling happening on US wireline networks these days. There was a huge blowback against Comcast for trying that ~10 years ago, using Sandvine gear to throttle bittorrent traffic at peak times.

There is still plenty of implicit throttling going on though, with broadband providers refusing to provision enough capacity between their networks and the content source networks. The existing links then become congested at peak times and performance is degraded for the customers trying to access that content.

VPNs may improve performance in this situation not because they are hiding or disguising the content, but simply because the traffic is "re-routed" around the congested links. Assuming that the links from content network -> VPN host and VPN host -> end user are not also congested.

I am one of the network engineers for time warner cable and we don't do any throttling or traffic shaping on customer traffic. We have Netflix boxes colocated but they might possibly get overloaded at certain times because people are using Netflix at an increasing rate. Sorry you aren't having a good experience, if you want to tell me which part of the country you live in I will try and have someone look into it.

Wrong, they aren't packet shaping. They have bad peering.

They refuse to add an adequate amount of peering to video services like Netflix and YouTube. The result is oversaturated routing during peak hours.

By using a VPN you change the route taken to the video service, bypassing the oversaturated connections.