Fedora considers curl-minimal

This is exactly right. If curl was modular upstream then we could have an interesting discussion about which of the modules to include in base Fedora. But nothing would be broken - if a package was expecting to use, say, telnet it could depend on libcurl-telnet so installing the package would install the extra curl module.

As you say it requires work upstream. No one has stepped up to do that.

FWIW we already went through this process with fio (Jens Axboe's Flexible I/O tester) which used to link all of its backends together, but now uses modules ("engines"), and we then changed the packaging in Fedora to use it: https://src.fedoraproject.org/rpms/fio/blob/rawhide/f/fio...