It's one huge ROI equation.
Sure you can sell 30" ovens, ranges and 27" washers in Europe.
Manufacturers do.
Even our production makes stuff we don't sell in the EU.
But as long as the establishment of a new manufacturing facility plus higher wages are more expensive than making it in one place, shipping it, importing it (2 hugely different things accounting wise) and then distributing it, and that for the foreseeable future, you just don't.
Keep in mind Whirlpool for example made the first "typical" US FLs in Europe. Why?
They had development and production knowledge for FLs here in Germany. They did not know if they were to sell 10 or 10000 a month.
Then they knew, and shipping production away made financial sense.
If the US imports enough 24" ovens and washers so that that equation flips towards moving manufacturing, they will.
They wouldn't invest an 8-9 figure amount (can't imagine them setting up a full production for less) if it wouldn't make sense with projections of sales numbers and an ROI time of like - I dunno, 15-25 years?
They certainly will have configured their production to be a bit more flexible.
Running both 24" and 30" ovens on the same line should be perfectly doable.
You just switch which SKU is produced every now and then, the main construction is about the same.
The main "thing" about an appliance is the same regardless of where it sells.
A fridge is a compressor, evap, condenser and insulated container.
A FL washer is a tub/drum unit in a cabinet, a few valves, a pump and a motor.
Thus, developing and assembling them efficiently works the same.
The key "equation" of what makes that appliance that appliance stays the same, be it large oven in a range or a small wall oven.
You just change the parameters a bit.