Enabling UDP GSO (generic segmentation offload) on PPPoE interface, not working, but works on physical ethernet interface

I can't seem to enable generic-segmentation-offload on my pppoe interface in order to enable quic_gso on my nginx config for faster quic performance...

I tried to enable it through ethtool using the following command, but the status remains off

$ ethtool -K pppoe-wan gso on
Actual changes:
tx-generic-segmentation: off [requested on]
Could not change any device features

Without gso on nginx errors out with
2024/06/27 01:24:43 [alert] 7#7: *584 sendmsg() failed (5: I/O error) while sending frames, client: x.x.x.x, server: 0.0.0.0:443 based on searching online I/O error 5 indicates GSO is not supported on the interface https://github.com/envoyproxy/envoy/issues/21200

When nginx listens to a physical ethernet port with GSO on, i'm not encountering any errors and GSO is successfully turned on as checking with ethtool, any kernel patches i can apply with this?

Random lines from nginx documentation:

The module is experimental, caveat emptor applies.
Default: quic_gso off;

Envoy proxy GSO also errors out (due to interface refuses to turn GSO on) even if HTTP/3 is no longer experimental on their end, like this error reported here

There is complex dependency tree in ethtool kK
Please post

ubus call system board
ethtool -k pppoe-wan | grep -v "\[fixed\]$"
ethtool -i pppoe-wan 
ethtool -k wan | grep -v "\[fixed\]$" 
...
(all lowlevel ifaces backing pppoe interface)

The only thing you can do - blindly cram all changeable options "on" until desired option changes to on from requested. if fixed options need to be changed they cannot.