> The HTTP/1.1 spec actually recommends limited to 2 connections per domain.

This is no longer true.

From RFC 9112 § 9.4 (https://httpwg.org/specs/rfc9112.html#rfc.section.9.4):

> Previous revisions of HTTP gave a specific number of connections as a ceiling, but this was found to be impractical for many applications. As a result, this specification does not mandate a particular maximum number of connections but, instead, encourages clients to be conservative when opening multiple connections.