Effectively zero latency from the data being written to the socket until it appears on the wire, by eliminating the latency of the TCP 3 way handshake.
They've basically discovered TCP Performance Enhancing Proxies, used for decades for space communications.
Yes, but only for a specific set of circumstances (when you can live without reliable & timely delivery, and do not need any sort of response) and only from the PoV of the client.
The claim seems correct with those caveats, though is a bit "click baity" without them.
I don't see how the claim is technically correct in any way. Unless they've figured out how to circumvent the speed of light, there is no such thing as "zero latency."
The client just jets out a single UDP packet. There is no TCP setup latency, effectively no latency at all though only from that client's point of view.
I think it is a valid claim, but only for a rare set of use cases where the significant caveats regarding delivery & response are OK. Though of course those caveats are not as heavy as they might at first seem if the link between client and proxy is strong and reliable, because the proxy will be performing the full handshake and can manage redeliver on error and other such things - but the client doesn't need to worry about any of that.
* for sufficiently large values of zero