Comment by mvzink

Ideally, in the future, yeah. But for now, two reasons I can think of: first, Multipath TCP doesn't cover the same use cases as dispatch. For example, having one proxy only route to low-latency connections (e.g. for gaming) and another to all connections (e.g. for downloads). Second, Multipath TCP isn't widely implemented and would require application developers to use it, whereas this can give many of the same benefits without waiting for your applications to support it.