I really like this concept. But the effect will be very significant.
The advent of trenches, gas, tanks, airplanes, airships, etc. completely changed the battlefield.

The trenches were certainly battles of attrition, in which sometimes entire units died from gas attacks. It would be very difficult to get the RTS part right here. For example, I also find HOI4 to be a very nice game, so I can really find myself in WW1 of Total War.

It also becomes difficult to take logistical items with you.
Where things like food and weather have played a major role in other laundry games. In addition to food, other supplies of gasoline also play a role. (In ancient times, every region had a food source for plunder, and fuel was not widely available in every region at that time. Even now, a certain country is struggling to supply fuel to its forces.

So I totally agree with you that this is a very interesting era for an all-out war game, and I’m glad I don’t have to think about how to put this setup in terms of balance.
But if they find it, I will definitely try 🙂