Websockets use one TCP socket for starters with SE you use separate sockets from ingress and egress which is much simpler to scale from an infrastructural point

Websockets use one TCP socket for starters with SE you use separate sockets from ingress and egress which is much simpler to scale from an infrastructural point of view. I clearly said many-to-many, everything else is trivial to scale because only many-to-many requires strictly shared memory atomic parallelization. You could write a better server in Java than javascript/c(++) but I haven't found any, and to be honest the extra complication of the binary protocol doesn't even make me curious enough to waste 5 seconds to google it. SSE over HTTP/1.1 is the final solution. Everything else is a waste of time for eternity.