I have a server in Utah. I was getting 10Mbps upload to it. While trying to figure out why, I realized speed tests were also throttled in that region on speedtest.net, although they scored a bit higher (~100Mbps).
I have the 1Gbps internet option.
Called astound. They wanted to send a tech. I declined, and asked that they forward the information to their network engineers. They couldn't do it. So I asked to speak to their supervisor and was hung up on.
So I started to do speed tests on a couple servers I have around the country. Similar issues.
I decided to try solving this myself. Setup a wireguard connection between my server in Utah and my home.
Same issue on wireguard. So I kept changing ports. Finally found one that wasn't throttled and was getting ~900Mbps upload.
So this is just a FYI. If you have Astound 1Gbps internet and you are on a residential connection you're likely being throttled (unless I'm just very unlucky).
Unfortunately speedtest.net is not a good testing option since they removed single threaded testing. I believe it's multithreaded by default now. You want to test single connection speeds to find this issue.
But, you may still notice slower then normal speeds regardless.