I agree with the logistics part, as they'd need to build and maintain additional facilities but
Abrams aren’t built for Romania’s terrain.
What do you mean by that? Why would they be incompatible with our terrain? Indeed, they'll most likely never be used in the Carpathians, as you'd need more compact and mobile vehicles to go through there. But given our current threat vector - which comes from the East, so basically only Moldovan low-rise hills, Dobrudja and the Romanian Plains where Bucharest is located being the parts under threat - why would they be not fit for that type of terrain?