This is somewhat of a recent issue (happens to coincide with my issues with sites timing out as well), and I'm not sure what I should be blaming here.
I have a Nexus 5X, a Nexus 5, and a Samsung Tablet, all of which show zero upload speed while connected to my network. Connecting to other peoples networks (or even public networks like McDonalds or similar) and I can upload just fine.
I'm on BigPipe VDSL, with a Vigor 130 that's bridged to an Edgerouter Lite (using Michael Murfy's setup here), Netgear ProSafe G5108E switch, to a Unifi AC Lite. Over the course of troubleshooting the issues I've been having, I've reset all of the network devices to default, and replaced all cables (just to rule those items out). BigPipe as part of troubleshooting my connection issues, has removed my IPV6 (made no difference). The Nexus 5X has been completely wiped and had the latest updates installed from the full image to help troubleshooting.
I've tried setting channels manually, as well as auto for the AP, and it has not made a difference at all. I'm at a bit of a loss as to what else I could try to get this working. This issue happens to coincide with my issues of having multiple websites reset their connection when attempting to browse them across multiple devices and operating systems. BigPipe recently stated it could be MSS clamping, however I've verified that's enabled on my router. They had me set my MTU to 1300, which killed my connection to any secured sites (non-secured sites connect just fine with that set). Any suggestions as to what else I could try, would be greatly appreciated, I'm tearing my hair out here.
46 second speedtest on my Nexus 5X: https://photos.app.goo.gl/URzLfnhNEUniscA28