Eeeeeh.
That's very debatable. If you have a direct DC genset, then, yes, it is arguable more efficient and in many ways more useful than running a vehicle.
But... Once you factor in conversion losses and maintenance schedules, generators are a huge hassle and that's why anyone that can sets them aside as backup and not primary systems.
Also, efficiency isn't what I'm after. I need robust, diverse sources of useful energy to do work. Just being efficient set point of use isn't a very large part of my system. Sure, it's good, but no one has yet been able to convince me that for my uses in my area that EVs are a better solution for most people.
Now... Electric bikes and scooters? That's where things tip waaaay in favor of all electric. (As long as you keep your battery packs