The repo-based speedtest-cli program under Debian 10, Ubuntu 18 is a broken product because its using outdated python2 libraries. The repo-based is the one you install via apt-get install speedtest-cli command.
It will show you the correct download speed result.
It will show you INCORRECT upload speed result averaging 4 mbps.
With an official Speedtest CLI https://www.speedtest.net/apps/cli you will get the real result.
Example of speedtest with official speedtest cli.
Examples with latest version of official speedtest:
Server: Italy
Latency: 0.44 ms (0.08 ms jitter)
Download: 735.95 Mbps
Upload: 935.67 Mbps
Packet Loss: 0.0%
Server: USA
Idle Latency: 0.43 ms (jitter: 0.14ms)
Download: 5017.45 Mbps
Upload: 4368.89 Mbps
Packet Loss: 0.0%
