> you can integrate all into one hub (breaks, bearings, gears etc) and it weights pretty much the same.

You would get to delete about half the mass of the half-shaft but otherwise you are cramming a lot of stuff into the wheel volume and it all has to survive living out there. Now your HV wiring and any cooling connections to the motor have to flex with the movements of the suspension and probably need guarding against rocks and other road debris. I think all EVs now have the drive electronics tightly coupled to the motors - now that either has to be separated or made compact enough to fit and rugged enough to survive a much higher vibration regime. We do have small amounts of electronics on hub assemblies today (I'm thinking of electronic parking brakes) so there is some precedent but that circuitry is much less challenging than an inverter handling 100s of kW.

>no loss on diff

I doubt there's much loss from differentials in EVs. They don't have the bevel gear of diffs used in longitudinal layout ICE vehicles and mostly the gears in a diff don't move relative to one another (unless you are doing donuts!), so the whole cage mostly acts like a solid gear giving whatever final ratio.

Do they claim enough reliability and peak power capability to delete the mechanical brakes? I know Brembo is working on electric brakes that would eliminate the hydraulic circuits and pistons. I don't know what they plan to do to make sure the electrical side is as robust as the split-diagonal brake system we've been using for 60 years or so.