The short answer is that it's more complicated to engineer and has its own set of trade-offs. With the push-based models shown in the article, everything works regular HTTP(S), no fancy routing is needed, and the LB needs to keep very little state to do its job.
seems like a request could be pulled from a queue with HTTPS easily enough. and if I am misunderstanding what you're saying, I don't understand why a purely request-driven path is so vital; it's just a way to me ve data around.
seems like the queue could accept the request, keep the https connection open, wait for a response from whatever server accepts the request, and pass the response to the client upon receipt just fine.
I dunno. web stuff is poorly done imo. poorly designed.
