Farming equipment for field work is surprisingly hard to electrify. In cars you can have your aerodynamic blob slip through the air almost unimpeded. Farming generally requires plowing stuff through soil and that’s very energy intensive process.

You can also think of it in the way how passenger cars generally use just a small fraction of their max power for vast majority of the time (when they are cruising at set speed). Farm tractors and such tend to work for hours on end at 80%-100% of their rated power. So a moderately sized 100kW tractor will need a 1MWh battery to go through a day of work. That’s basically an engineering impossibility without some extreme compromises. Eventually we will have to figure out something (easily swappable batteries automatically ferried between charging station and the tractor? or something), but right now it’s a huge problem.