I also recommend a cordless impact driver. The amount of torque you can generate with a drill is limited by your ability to hold the drill. The amount of torque you can generate with an impact driver is magnitudes more. Great for driving screws, tightening nuts, I’ve even used it for drilling through wood with a spade bit.
It’s less about size and more about population density.
Japan is 338 people per square kilometer https://en.wikipedia.org/wiki/Demographics_of_Japan
China is 147 people per square kilometer total https://en.wikipedia.org/wiki/Demographics_of_China
The US is 36 people per square kilometer https://www.census.gov/data/tables/time-series/dec/density-data-text.html
The US could build long distance high speed rail like Japan and China, but the ridership level would be rock bottom due to the low population density.
While I agree that vendor lock in sucks, getting a universal standard open source tool battery is not likely to happen. I decided to go with the Milwaukee M18. They have a huge variety of tools available, and they all use the same interchangeable battery. I have a drill, an impact driver, a circular saw, and hedge trimmers.