It may be desirable to alter the curl
build time options to facilitate this argument working, specifically --dns-ipv4-addr 123.123.123.123
fails:
$ curl -4 --interface 123.123.123.123 --dns-ipv4-addr 123.123.123.123 https://wtfismyip.com/text
curl: (4) A requested feature, protocol or option was not found built-in in this libcurl due to a build-time decision.