@Scott Tupper - They go to us at Microsoft in the product group who owns/runs Microsoft Stream. We can't get back to everyone on each of these, but we do attempt to get back when we can.
We do look at them in aggregate to understand and investigate where customers are having issues with Stream playback. Sending those reports do also collect up verbose logs for us so it's easier for us to investigate and prioritize. So please do keep them coming our way. But we won't be able to get back to you personally on every submission.
However if you have a specific problem and you want us to work with you on it, please do open a support ticket in addition to sending one of these reports. You can refer to the session ID from the "report a technical issue" pop-up in the support case.