Yes, we would banish ourselves in the process, however, since we aren't really meant to exert any great influence over this universe, but ultimately just fight the other outsiders. Returning everyone to their native universe seems to be better. I doubt we will be able to revert a whole multiversal jump process, but it seems to be a running theme that we need to leave native alone and fight the other outsiders, hence searching for a reason why we are here seems to be perfectly logical path (even if it ultimately fails)