I re-implemented the rate limiting in #curl, coming in the next release. A description.
eissing.org/icing/posts/curl-r…
curl rate limits
The curl project merged #19384, #20033 and #20228 which re-implements rate limiting of transfers in libcurl. This will be part of the upcoming 8.19.0 release at the beginning of March 2026.icing's blog