It'll come. There are a lot of electric forklifts around, in part due to the natural ballast of a large battery, and operating them indoors.
I'd love to have a tractor that was 1000 or 2000 lbs heavier than what I have.
However, I'm not willing to go out and spend $50K for the latest and greatest technology on the block.
But you're right. an all electric large tractor or combine could be a problem. What if your battery only lasts 5 hours a day and you need to be on the field for 15 hours? Or you're operating 10 miles from your home charging point?
Perhaps they'll come with swappable batteries. So, one drops the battery on a battery trailer and picks up a new one, and is back to operating. While the assistant runs home to recharge.
Noting, of course, that the power companies don't like to give residential customers more than 200A 220V or in some cases 400A 220V, and they probably don't want you running it up to the full 100% load. Or, for a few days a year, every neighbor using the full 100% load.
Anyway, for my use, 5 gallons of tractor diesel can last me a very long time... many months, or sometimes years. There is little benefit of going to really expensive batteries.
I do have an electric mini van which I do like. However, one thing that I always have in the back of my mind is what would happen if I got a battery fire.