To some extent, the 7.5 times (stuck with this arbitrary figure now …) more things that it does are not necessarily externalisable bloat—it hasn't grown an e-mail client (I think?)—but rather a response to the increasing demands of modern web pages. Offloading, say, JavaScript processing (a not-insignificant part of modern browser code, I think) to a separate application is surely possible, but also surely pointless.