Based on the experience, the proxy would caused lots of issues(e.g cannot register, cannot dnf, curl...etc.),
it would set in different conf(rhsm.conf, dnf.conf..) for different services, but the system setting(e.g profile, or simply export) also work, currently sos just collect variable name under system plugin, so it would better to collect proxy (e.g. https_proxy=xxx) individually, and make it easy check with root_symlink.

# ll
system-proxy-setting -> sos_commands/system/system_proxy_setting

e.g.
# cat system-proxy-setting
No system proxy settings found.

# cat system-proxy-setting
http_proxy=http://********@proxy.example-test-test.com:8080
https_proxy=http://********@proxy.example-test-test.com:8080

# cat system-proxy-setting
http_proxy=http://proxy.example-test-test.com:8080
https_proxy=http://proxy.example-test-test.com:8080