I agree with your larger point. For instance, I believe Google purposefully avoided implementing some privacy-preserving features in its QUIC protocol.
However, in this case, it was the ISPs and wireless carriers that fought against deprecating HTTP, while Google and Mozilla wanted to deprecate it. It's why I think they only enabled the HTTPS version of HTTP/2 in their browsers. The carriers and ISPs wanted the web to stay on HTTP so they can mine everyone's data, as they're already doing with the sites that have remained on HTTP.