you could install a local iperf3 server and test your upload and download speed locally:
opkg update
opkg install iperf3
iperf3 -s
Then test from a Linux machine with iperf3 client: Best practices and tools for measuring wifi performance
or with iperf3 binary apps:
- iOS app with iperf3: https://apps.apple.com/us/app/iperf-3-wifi-speed-test/id1462260546
- Android app with iperf3: https://play.google.com/store/apps/details?id=net.he.networktools
- Docker image with iperf3: https://hub.docker.com/r/networkstatic/iperf3
- Windows binaries for iperf3: https://iperf.fr/iperf-download.php
A fast local wi-fi connection helps always and not only to reach your full ISP uplink speed. The shorter your wireless channel is needed and used for transmission, the better. Higher speeds also help when your wi-fi spectrum is crowded by other networks and other applications.