In the real world TCP window scaling solves latency induced delays for video streaming in all but the most extreme cases (hence my caveat), and endpoint buffering can solve even those.
For many activities on the internet a 1,000ms latency would be intolerable, but for one-way video streaming it's unnoticeable to the end user. I don't really care if a packet containing video takes 50ms or 1000ms to get from the CDN to my TV, as long as it gets there and is reasonably consistent in it's ability to do so.
For this use case, if my machine can get 20Mb/s on the test, latency will just not affect me streaming a 10Mb/s video. Latency may be lowering my test results, but that's the point here - testing the effective throughput.
You can easily determine how much of a problem it is in your case by calculating your bandwidth delay product: https://en.wikipedia.org/wiki/Bandwidth-delay_product