Consider the Eviation Alice, one of the 9 passenger prototype electrical planes that is currently undergoing test flights (i.e. it definitely works). The advertised range is 250nm. Not amazing. But far enough for a lot of regional flights.
What would happen if you double the battery capacity without increasing the weight? You more than double that range. This is counter intuitive until you realize that you are not going to need more energy for taking off, or reserves. All that extra energy goes into extending cruise range. So you get more than 250nm extra. Basically, it's probably getting closer to 600nm. That's still not amazing but there are a lot of flights every day that are much shorter than that. All of those are now doable with electrical planes. At a fraction of the fuel cost.
Most flights are short haul. And they are, well, short. Which means, all of those are in scope for electrical planes. Small planes work well for these too. You don't have to cram hundreds of people in a plane if you eliminate fuel cost as a major cost factor. That's the only reason we do that. It's not like it's pleasant or comfortable. 20 ten passenger planes can do the work of one passenger jet. But it can do it more flexible and cover more destinations too.
Electrical planes are not about doing exactly the same things that we do with traditional planes but about doing a lot more than that. Basically, less noise, less pollution, less cost, means that a whole lot of flights that would be considered decadent and obscene right now become perfectly feasible and reasonable. A ten minute hop across town. Why not? Live 70 miles from your office? Not a problem, you commute there in under 15 minutes. For the price of a few cups of coffee.