> I'm seeing gigabit(-ish) via speedtest-cli:
You're using their cli client, not the open source one. Below, first their "speedtest" and then the open source "speedtest-cli"
mlyle@brazen:~ $ ./speedtest
Speedtest by Ookla
Server: Cloudflare - San Jose, CA (id = 44932)
ISP: Frontier Communications
Latency: 12.10 ms (1.29 ms jitter)
Download: 953.32 Mbps (data used: 1.0 GB )
Upload: 891.89 Mbps (data used: 1.1 GB )
Packet Loss: Not available.
vs.
mlyle@brazen:~ $ speedtest-cli
Retrieving speedtest.net configuration...
Testing from Frontier Communications (47.155.215.132)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Nitel (Los Angeles, CA) [446.50 km]: 49.103 ms
Testing download speed................................................................................
Download: 323.09 Mbit/s
Upload: 300.49 Mbit/s
speedtest-cli is a python program, vs. the native speedtest:
mlyle@brazen:~ $ file /home/mlyle/.local/bin/speedtest-cli
/home/mlyle/.local/bin/speedtest-cli: Python script, ASCII text executable
mlyle@brazen:~ $ file speedtest
speedtest: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), statically linked, stripped