Comment 3 for bug 1937926

:~$ iw dev wlan0 link
command failed: No such device (-19)
:~$ iw dev wlan0 get power_save
command failed: No such device (-19)

Seems like there is no device named wlan0. I think it is wlo1 instead of wlan0 on my laptop. When I replace wlan0 with wlo1, the results are as follows:
:~$ iw dev wlo1 link
Connected to 50:2b:73:74:69:91 (on wlo1)
 SSID: Crossroads
 freq: 2412
 signal: -63 dBm
 tx bitrate: 150.0 MBit/s
:~$ iw dev wlo1 get power_save
Power save: on

:~$ iw dev wlan0 set power_save off
command failed: No such device (-19)
:~$ iw dev wlo1 set power_save off
command failed: Operation not permitted (-1)
:~$ sudo iw dev wlo1 set power_save off
[sudo] password for soumadeepsarkar1:
:~$ iw dev wlo1 get power_save
Power save: off

Even after setting power_save to off, it speed doesn't improve.
These are the speeds tested using speedtest.net after setting power_save to off

 PING ms
3
 DOWNLOAD Mbps
4.23
 UPLOAD Mbps
6.42