Green T-34's were absolutely terrible. If anyone remember the CoH2 beta where every penetrating hit inflicted a mini-crit on the vehicle, that's what Green T-34's were. If the T-34 was hit by another tank, it would disable some part of it. Red Banner T-34-85 would be awesome though, the Soviet faction has no elite armored vehicles.
Company of Heroes emphasizes unit preservation and tactics, there is no such thing as "expendable armor".
No one said they had to be the same implementation as the beta though. Red banners for example would definitely need TA treatment, where they still need to vet up but have unique abilities.
Green T34s could theoretically work as cheaper T34s with worse stats on accuracy and aiming and worse veterancy, but still have full armor and damage. When vetted, they could basically be normal T34s. They would basically be a very cheap medium tank that costs more fuel than manpower ratio wise to buy compared to other tanks. I don't really care either way how they get implemented, its just a unit concept that I feel could fit well with this commander, especially since if I remember right they had unique voice-lines.