But at any given time you may be in a branch that's going to be deleted or rewound because it doesn't lead to the results that the simulators want. The vast bulk of our experience would be in lines that the simulators don't want.

Not necessarily. It would depend on how narrow they wanted things and how often they intervened in this fashion. If such interventions are not very common then the majority of experience will be in universes which are very close to that desired by the simulators.

but the conclusions jacob cannell drew are still extraneous additions to the simulation argument, not necessary consequences of it.

No disagreement there.